The length of rod cut from A is 40 cm
Solution:
Given that,
length of rod A = 120 cm
length of rod B = 96 cm
After a rod of equal length is cut from each rod, the ratio of the length of a to that of b becomes 10 : 7
Let "x' be the length of rod cut from rod A and rod B
After that, now length becomes,
length of rod A = 120 - x
length of rod B = 96 - x
Their ratio is equal to 10 : 7
Therefore, we get

Thus the length of rod cut from A is 40 cm