Question

Find the third propotional to
$5 \times \frac{1}{4 } \: \: \: \: and \: \: 7$
​

Answer 1

5/4 : 7 :: 7 : x

=> 5/4 × 1/7 = 7/x

=> 5/28 = 7/x

=> 5x = 28×7 = 196

=> x = 196/5 = 39.2 [Ans.]