6.4$
Solution:
Divide 40 and 100(there must always be 100 when solving percentage) then it would be equal to 0.4
after it Multiply it to 16
so we get 6.4.
25/28
is in it's lowest form, as it cannot be reduced anymore.
25/28 = 0.8928571
hope this helps
Recognize the differnce of 2 perfect squares
a²-b²=(a-b)(a+b)
so