Answer:
c = 20
Explanation:
lets express the word sentence as mathematical equations:
"1/4 of a number c" can be written---> (1/4) x c = c/4
"5 is 1/4 of a number c" can be written ---> 5 = c/4
solving the equation for c
5 = c/4 (multiply both sides by 4 and rearranging)
c = 5 x 4
c = 20