Problema Solution
A family of four orders one extra large pizza. The father eats 7/18 of the pizza, the older child eats 1/12 of the pizza, and the younger child eats 3/8 of the pizza. How much pizza is left for the mother? (Please show all of your work and write your answer as a fraction in lowest terms, with appropriate units.)
Answer provided by our tutors
1 - 7/18 - 1/12 - 3/8
common denominator:
18 prime factors to 2*3^2
12 prime factors to 3*2^2
8 prime factors to 2^3
2^3 * 3^2 = 8*9 = 72
we want a common denominator of 72:
72 / 18 = 4
72 / 12 = 6
72 / 8 = 9
1 - (4*7 + 6*1 + 3*9)/72
1 - 61/72 = 11/72
the mother is left with 11/72 of the pizza