a) volume of actual aircraft = 3375 x 103 cm3
Volume of model = 125 cm3
Volume scale factor v = (3375 x 103) /125
= 27000
Linear scale factor l = 3rd root of 27000
= 30
Wingspan of model = (7.44 x 100)/30 cm
= 24.8 cm
b)Area scale factor a = l2 = 900
Surface area of actual aircraft
= 2420 x 900 cm2
= (2420 x 900)/100 x 100 m
2
=217 m2
c)cost of materials = 217.8 x 104 x 2.5
= 5.445 x 106
= US$ 5.445 million
Githiari answered the question on April 6, 2019 at 19:29
- A sales lady sold four plots at sh.180000@,she was paid a commission of sh.54000.What percentage commission that she...(Solved)
A sales lady sold four plots at sh.180000@,she was paid a commission of sh.54000. What percentage commission that she was paid?
Date posted: April 6, 2019. Answers (1)
- A cold water tap can fill a bath in 6 minutes while a hot water tap can fill it in 12 minutes. The drainage pipe...(Solved)
A cold water tap can fill a bath in 6 minutes while a hot water tap can fill it in 12 minutes. The drainage pipe can empty the bath in 8 minutes. All the three are opened fully for 3 minutes and then hot water tap is closed. How many more minutes will it take to fill the bath?
Date posted: April 3, 2019. Answers (1)
- An estate is drawn to scale on a grid of 1 cm squares with a total area of 35 cm2 .If the actual area of...(Solved)
An estate is drawn to scale on a grid of 1 cm squares with a total area of 35 cm2 .If the actual area of the estate is 560 hectares, calculate the linear scale of the map.
Date posted: April 3, 2019. Answers (1)
- Use the method of completing the square to solve the quadratic equation
2x2 - 13x + 15 = 0
(Solved)
Use the method of completing the square to solve the quadratic equation
2x2 - 13x + 15 = 0
Date posted: April 3, 2019. Answers (1)
- The sum of the first 8 terms of an AP is 236 and the sum of the first 6 terms of the same series is...(Solved)
The sum of the first 8 terms of an AP is 236 and the sum of the first 6 terms of the same series is 147. Find the sum of the first 12 terms of the series.
Date posted: April 3, 2019. Answers (1)
- A mixed day and boarding secondary school has a student depositions population of 630. The ratio of girls to boys is 3:4. The school has...(Solved)
A mixed day and boarding secondary school has a student depositions population of 630. The ratio of girls to boys is 3:4. The school has 350 boarders some of whom are boys and others are girls. A student is picked at random from the school. Find the probability that the student is
a) a boarder
b) a girl and not a boarder.
Date posted: April 3, 2019. Answers (1)
- Juma deposited sh 16000 in a bank which paid compound interest at the of 12 percent per annum. At the end of five years, he...(Solved)
Juma deposited sh 16000 in a bank which paid compound interest at the of 12 percent per annum. At the end of five years, he withdrew all his money. Determine how much money he withdrew.
Date posted: April 3, 2019. Answers (1)
- Describe the procedure to be followed when constructing ungrouped frequency distribution table(Solved)
Describe the procedure to be followed when constructing ungrouped frequency distribution table.
Date posted: April 3, 2019. Answers (1)
- To transport 100 people and 3500 kg to a wedding a company has type A vehicles which take 10 people and 200kg each and type...(Solved)
To transport 100 people and 3500 kg to a wedding a company has type A vehicles which take 10 people and 200kg each and type B which take 6 people and 300kg each. They must not use more
than 16 vehicles all together.
(a) Write down 3 inequalities in A and B which are the number of vehicles used and plot them
in a graph.
(b) What is the smallest number of vehicles he could use.
(c) Hire charge for type A is Sh.1000 while hire for type B is Sh.1200 per vehicle. Find the cheapest
hire charge for the whole function
Date posted: March 29, 2019. Answers (1)
- Chalk box x has 2 red and 3 blue chalk pieces. Box Y has same number of red and blue
pieces. A teacher picks 2 pieces...(Solved)
Chalk box x has 2 red and 3 blue chalk pieces. Box Y has same number of red and blue
pieces. A teacher picks 2 pieces from each box. What is the probability that
(a) They are of the same colour.
(b) At least one is blue
(c) At most 2 are red
Date posted: March 29, 2019. Answers (1)
- OAB is a triangle with OA = a , OB = b. R is a point of AB. 2AR = RB. P is on OB...(Solved)
OAB is a triangle with OA = a , OB = b. R is a point of AB. 2AR = RB. P is on OB such that 3OP = 2PB. OR and AP intersect at Y, OY = m OR and AY = nAP. Where m and n are scalars. Express in terms of a and b.
(i) OR
(ii)AP
(b) Find the ratio in which Y divides AP
Date posted: March 29, 2019. Answers (1)
- The following was Kenya`s income tax table in 1988.
Income in K£ P.a Rate (Ksh) £
1 - 2100 ...(Solved)
The following was Kenya`s income tax table in 1988.
Income in K£ P.a Rate (Ksh) £
1 - 2100 2
2101 - 4200 3
4201 - 6303 5
6301 - 8400 7
(a) Maina earns £ 1800 P.a. How much tax does he pay?
(b) Okoth is housed by his employer and therefore 15% is added to salary to make taxable income. He
pays nominal rent of Sh.100 p.m His total tax relief is Shs.450. If he earns K£3600 P.a, how much
tax does he pay?
Date posted: March 29, 2019. Answers (1)
- A rectangular tennis court is 10.5m long and 6m wide. Square tiles of 30cm are fitted on the floor.
(a) Calculate the number of tiles needed....(Solved)
A rectangular tennis court is 10.5m long and 6m wide. Square tiles of 30cm are fitted on the floor.
(a) Calculate the number of tiles needed.
(b) Tiles needed for 15 such rooms are packed in cartons containing 20 tiles. How many cartons are
there in total?
(c) Each carton costs shs. 800. He spends shs. 100 to transport each 5 cartons. How much would one
sell each carton to make 20% profit ?
Date posted: March 29, 2019. Answers (1)
- Members of a youth club decided to contribute shs 180,000 to start a company. Two members withdrew their membership and each of the remaining member...(Solved)
Members of a youth club decided to contribute shs 180,000 to start a company. Two members withdrew their membership and each of the remaining member had to pay shs. 24,000 more to meet the same expense. How many members remained?
Date posted: March 29, 2019. Answers (1)
- A right cone with slant height of 15cm and base radius 9cm has a smaller cone of height 6cm chopped off to form a frustum....(Solved)
A right cone with slant height of 15cm and base radius 9cm has a smaller cone of height 6cm chopped off to form a frustum. Find the volume of the frustum formed
Date posted: March 29, 2019. Answers (1)
- A solid sphere of radius 18cm is to be made from a melted copper wire of radius 0.4mm . Calculate the length of wire in...(Solved)
A solid sphere of radius 18cm is to be made from a melted copper wire of radius 0.4mm . Calculate the length of wire in metres required to make the sphere. (5mks)
(b) If the density of the wire is 5g/cm3. Calculate the mass of the sphere in kg.
Date posted: March 29, 2019. Answers (1)
- A building contractor has to move 150 tonnes of cement to a site 30km away. He has at his disposal 5 lorries. Two of the...(Solved)
A building contractor has to move 150 tonnes of cement to a site 30km away. He has at his disposal 5 lorries. Two of the lorries have a carrying capacity of 12 tonnes each while each of the remaining can carry 7 tonnes. The cost of operating a 7 tonne lorry is sh. 15 per km and that of operating a 12 tonne lorry is sh. 25 per km. The number of trips by the bigger lorries should be more than twice that made by smaller lorries.
(a) Represent all the information above as inequalities.
(b) How should the contractor deploy his fleet in order to minimise the cost of moving the cement?
Date posted: March 29, 2019. Answers (1)
- Given a circle of radius 3 units as shown in the diagram below with its centre at O(-1, 6). If BE and DE are tangents...(Solved)
Given a circle of radius 3 units as shown in the diagram below with its centre at O(-1, 6). If BE and DE are tangents to the circle where E (8,2). Given further that angle DAB = 800.
(a) Write down the equation of the circle in the form ax2 + bx + cy2 + dy + e = 0 where a, b, c, d, e are constants.
(b) Calculate the length DE.
(c) Calculate the value of angle BED.
(d) Calculate the value of angle DCB.
Date posted: March 29, 2019. Answers (1)
- Find the distance between points A(500 S, 250 E) and B(500 S, 1400 E) in:
(i) Km ...(Solved)
Find the distance between points A(500 S, 250 E) and B(500 S, 1400 E) in:
(i) Km (ii) nm
(take radius of earth to be 6400km, π = 3.14)
Date posted: March 29, 2019. Answers (1)
- A bag contains x red balls and y yellow balls. Four times the number of red balls is equal to nine times the number of...(Solved)
A bag contains x red balls and y yellow balls. Four times the number of red balls is equal to nine times the number of yellow balls and twice the total number of balls exceeds the number of yellow balls by 44.
(a) How many balls of each colour are three in the bag?
(b) If two balls are drawn out of the bag at random one at a time with replacement what is the probability that the two balls are red?
Date posted: March 29, 2019. Answers (1)