Solution:
Length of the string of kite A = 688 m
Length of the string of kite B = 705 m
We know that, 705 > 688
So, the string of kite B is longer.
Difference between the length of the strings of the kite = length of string of kite B - length of string of kite A = 705 m - 688 m = 17m
So the string of kite B is 17 m longer than kite A.