Worksheet on Changing the Subject in an Equation or Formula

In worksheet on changing the subject in an equation or formula we will practice how to find the value of the variables by changing the subject in an equation or formula using the substitution method.

1. Given A = 1/2 × b × h, when A = 75 and h = 10, find b.

2. Given V = 1/3 πr²h when V = 308 and h = 6, find r.

3. Given S = 6a² when S = 600, find a.

4. Given P = 2 (l + b) when l = 15 and P = 50, find b.

5. Given C.P. = (S.P. × 100)/(100 × g %) find S.P. when C.P. = $ 140 and G% = 5%.

6. A = P + I find l if A = 4500 and P = 3750.

7. In C = 5/9 (F - 32) find F if C = 25.

8. In V = l × b × h find l if V = 3000, b = 15, h = 10.

9. If D = 2r find r if D = 50.

10. If x + y + z = 180 find y if x = 70 and z = 65.

11. In v = u + ft find f if v = 36, u = l2 and t = 8.

12.In gt²/4π² = l, find the value of t if l = 49, t = 4.

13. In A = 2h (l + b), find h if A = 50, l = 6, b = 4.

14. In S = n/2 {2a + (n - 1) d}, find d when S = 125, n = 10, a = 2.

15. If C = 2 πr, find r if C = 88, π = 22/7.

16. If D = S × T, find S when D = 450 and T = 15.

17. In a = (p - m)/(p + m), if a = 3/7 and p = 10, find m.

18. If I = (P × R × T)/100, find T if I = 80, P = 400, R = 10.

19. In L% = (L/C.P.) × 100, find L if L% = 12 and CP = 200.

20. In V = π r²h, if V = 1540, h = 10, find r.

Answers for worksheet on changing the subject in an equation or formula are given below to check the exact answers of the above questions on finding the value of the subject in an equation or formula.