Place each fraction under a common denominator. Remember, the number you multiply to the denominator must also be multiplied to the numerator
29/40 = 29/40
7/10(4/4) = 28/40
3/5(8/8) = 24/40
As seen by the fractions above, the order is 24/40, 28/40, and 29/40, or placed in it's original form is 3/5, 7/10, 29/40.
29/40 is the greatest, and is your answer
hope this helps