Question

If the mean proportional between X and Y is 8 times the third

proportional, then the ratio X : Y will be :

X vkSj Y dk eè;kuqikrh bud s r`rh;kuqikrh dk 8 xquk gS rc X vkSj Y dk vuqikr D;k gksxk\

(a)4:1 (b)5:3

(c)5:1 (d)4:3​

Answer 1

Answer:

Let, the two numbers be x and y respectively

Mean proportional between x and y is 16

i.e., x:16=16:y⟹xy=256

Third proportional to x and y is 128

i.e., x:y=y:128⟹y

2

=128x

⟹y

2

=128×

y

256

⟹y

3

=128×256=32768=2

15

∴y=2

5

=32

⟹x=

y

256

=

32

256

=8

Hence, the two numbers are 8 and 32 respectively