Question

what should be added to 5 by 7 to get 2by3​

Answer 1

let the no be X

X +5/7= 2/3

X=2/3-5/7

lcm of 3 and 7 =21

14/21 -15/21=x

-1/21 =X

so

$\frac{ - 1}{21 \:} is \: answer$