Ratio of first and second number =2:3
Ratio of second and third number =5:3
We need to have the same value of the second number in both the ratios:
To get this, we will multiply the first ratio by 5 and the second ratio by 3.
The final ratio → A:B:C=10x:15x:9x
According to the question:
10x+15x+9x=136
34x=136
x=4
First Number =10x=10×4=40