Answer:
5/4 cups, or 1&1/4 cups
Explanation:
You eat 1/4 cups of cereal, and your brother eats 5 times as much. You eat 1 fourth of 1 cup, and he eats 5 times 1 fourth of 1 cup. 1 times 5 is 5, which means he eats 5 fourths of 1 cup of cereal. Since he eats 5 fourths of 1 cup, and four fourths make a 1, he eats 1 cup of cereal, plus another fourth of a cup. Your brother eats 1 and 1 fourth cups of cereal.
1 / 4 x 5 = ( 1 x 5 ) / 4
5 / 4 = ( 4 / 4 ) + ( 1 / 4 )
1 + ( 1 / 4 ) or 1 & ( 1 / 4 )