Question

помагите 2 задания 579,580

Answer 1

N579
2) 2/9-21/80=7/120
N580
2)1/3+1/2=2/6+3/6=5/6

Answer 2

$frac{4}{9} times frac{3}{4} + frac{2}{3} = frac{1}{3} + frac{2}{3} = 1$
$2 frac{3}{10} times 2 frac{1}{2} + frac{1}{2} = frac{3}{5} + frac{1}{2} = frac{11}{10} = 1 frac{1}{10}$