Get premium membership and access questions with answers, video lessons as well as revision papers.
Correctly substitute the values of u and v. Then 1/f = (1/u)+(1/v) will be
1/f = (1/0.40) + (1/0.80)
1/f = 2.5 + 1.25
Hence 1/f = 3.75 and therefore the value of f will be the reciprocal of 3.75
f = 0.266...
joseph rimiru answered the question on September 21, 2017 at 19:38
- Find the reciprocal of the following values . You can use the long division method
a) ...(Solved)
Find the reciprocal of the following values . You can use the long division method
a) 6 b) 5 c) 27 d) 3.5 e) 4.8 f) 1.02
Date posted: September 21, 2017. Answers (1)
- Find the value of each of the following cubes:a. (XY)^3b. (4a)^3c. (3ab)^3d. (-2bc)^3(Solved)
Find the value of each of the following cubes:
a. (XY)^3
b. (4a)^3
c. (3ab)^3
d. (-2bc)^3
Date posted: September 21, 2017. Answers (1)
- John walks homes from school which is 3 km due east and 4km due north. find the shortest distance between his home and school.(Solved)
John walks homes from school which is 3km due east and 4km due north. Find the shortest distance between his home and school.
Date posted: September 20, 2017. Answers (1)
- Expand the following quadratic equations,using any of the quadratic identity: a) (2x+4)^2 b) (3x-5)^2 c) (5x-2)(5x+2)(Solved)
Expand the following quadratic equations,using any of the quadratic identity: a) (2x+4)^2 b) (3x-5)^2 c) (5x-2)(5x+2)
Date posted: September 20, 2017. Answers (1)
- Solve the value of x in 2x+4(2x+7)=3(2x+4)(Solved)
Solve the value of x
2x+4(2x+7)=3(2x+4)
Date posted: September 16, 2017. Answers (1)
- Dida is now three times as old as his brother and four times as old as his son. Eight years from now, Dida’s age...(Solved)
Dida is now three times as old as his brother and four times as old as his son. Eight years from now, Dida’s age will be twelve years more than the sum of the ages of his brother and his son. Find Dida’s present age.
Date posted: September 16, 2017. Answers (1)
- What is the angle of line whose equation is 3x+y=0 in cartesian plane.(Solved)
What is the angle of line whose equation is 3x+y=0 in cartesian plane.
Date posted: September 12, 2017. Answers (1)
- Find the equation of the line which is perpendicular to the line (Solved)
Find the equation of the line which is perpendicular to the line 8x + 2y -3 = 0 and has the same x - intercept as the line.
Date posted: June 13, 2017. Answers (1)
- A line passing through the point A(4,-3) and B(6,-6) is perpendicular to px + 6y = -2. What is the value of p. (Solved)
A line passing through the point A(4,-3) and B(6,-6) is perpendicular to px + 6y = -2. What is the value of p.
Date posted: June 13, 2017. Answers (1)
- A straight line through the point A(2,1) and B(4,n) is perpendicular to the line whose equation is 3y + 2x - 5 = 0. Determine the value of n. (Solved)
A straight line through the point A(2,1) and B(4,n) is perpendicular to the line whose equation is 3y + 2x - 5 = 0. Determine the value of n.
Date posted: June 13, 2017. Answers (1)
- The equation of a line is
$\frac{-3x}{5}$ + 3y = 6. Find the,(Solved)
The equation of a line is
$\frac{-3x}{5}$ + 3y = 6. Find the,
(a) Gradient of the line.
(b) Equation of the line passing through the point (1,2) and perpendicular to the given line.
Date posted: June 13, 2017. Answers (1)
- A perpendicular is drawn from a point (3,5) to the line x + 2y = 3. (Solved)
A perpendicular is drawn from a point (3,5) to the line x + 2y = 3. Find the equation of the perpendicular.
Date posted: June 13, 2017. Answers (1)
- Find the equation of the straight line which passes through (2,-1) and is perpendicular to 2y = 3x + 5. Give your answer in the form of ax + by + c =0 (Solved)
Find the equation of the straight line which passes through (2,-1) and is perpendicular to 2y = 3x + 5. Give your answer in the form of ax + by + c =0
Date posted: June 13, 2017. Answers (1)
- The line 3x + 2y = 8 cuts the y-axis at p(0,k) find
(Solved)
The line 3x + 2y = 8 cuts the y-axis at p(0,k) find
(a) Gradient of the line.
(b) The value of k
Date posted: June 13, 2017. Answers (1)
- Find the equation of a line whose gradient is -$\frac{2}{3}$ and passes through point (-2,3)(Solved)
Find the equation of a line whose gradient is -$\frac{2}{3}$ and passes through point (-2,3)
Date posted: June 13, 2017. Answers (1)
- Find the equation of the straight line passing through the points (-3,4) and (8,1)(Solved)
Find the equation of the straight line passing through the points (-3,4) and (8,1)
Date posted: June 13, 2017. Answers (1)
- The gradient of a line AB is 1. If A and B are (3,5) and (x,4) respectively, find the value of x. (Solved)
The gradient of a line AB is 1. If A and B are (3,5) and (x,4) respectively, find the value of x.
Date posted: June 13, 2017. Answers (1)
- The length of a line segment joining A(3,y) and B(7,5) is 5 units. Find the possible value of y. (Solved)
The length of a line segment joining A(3,y) and B(7,5) is 5 units. Find the possible value of y.
Date posted: June 13, 2017. Answers (1)
- C(4,3) is the midpoint of a line segment AB. Given that the coordinates of B are (6,5), what are the coordinate of A? (Solved)
C(4,3) is the midpoint of a line segment AB. Given that the coordinates of B are (6,5), what are the coordinate of A?
Date posted: June 13, 2017. Answers (1)
- Evaluate using tables (Solved)
Evaluate using tables
$\frac{(0.0056)^{\frac{1}{2}}}{1.38 \times 27.42}$
Date posted: June 13, 2017. Answers (1)