Question

Find the value of x in each of the following
(a) 10:20:40:x (b) 4:x::28:63
(c) 9:x::x:81 (d) 30:25::42:x (e)x:12::81:27(f) 7:x::21:30
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Answer 1

use rule

product of means =product of extremes

so it will be 10* x = 20* 40 so answer will be x = 80

b). 4*63 =×*28 so answer is x=9

c=)×*× = 81 *9 so x = 27

d) 30*x =25*42 so x = 35

e) 12*81 =27*x so x=36

f) 7*30= x*21 so x =10

here * is multiply

Answer 2

Step-by-step explanation:

A. 10 / 20 = 40 / x

10x = 80

x = 8

B. 4 / x = 28 / 63

28x = 252

x = 9

C. 9 / x = x / 81

x² = 729

x = 27

D. 30 / 25 = 42 / x

30x = 1050

x = 30

E. x / 12 = 81 / 27

27x = 972

x = 36

F. 7 / x = 21 / 30

21x = 210

x = 10