All number in percentage form when converted into a fraction will serve as the numerator with 100 as the denominator. The percent sign will be removed and the fraction will be simplified.
Put each one over 100. So 42/100, then reduce down by dividing by 2 both the top and bottom figures and you get 21/50 for your first answer. Do the same with each of the rest...72/100 and reduce down to 36/50, then reduce again 18/25 and that is the farthest you can reduce on that one. Do the same for the rest.
A "regular quadrilateral" is a square, so the length and width are both 4 cm. The surface area of a rectangular prism is given by S = 2(LW +H(L +W)) S = 2((4 cm)*(4 cm) +(6 cm)*(4 cm +4 cm)) S = 2(16 cm² +48 cm²) S = 2*64 cm² = 128 cm²
