Question

4by9 ,9by20,19by42,39by86 next number in series?​

Answer 1

4/9, 9/20, 19/42, 39/86........

assume that it is in the form of a1/b1, a2/b2, a3/b3, a4/b4

in numerator let 4 be a1, 9 be a2 , 19 be a3, 39 be a4.

we concluded that,

a1=4

a2=4+5

a3=9+10

a4=19+20

Therefore, a5 must be 39+20

Similarly,

in denominator

b1= 9

b2 = 9+11

b3 = 20+22

b4= 42+44

Therefore, b5 must be added with 88

So, Answer is 79/174