Question

(7 1/4 - 6 7/18)*7,2+2,8 решите плиз

Answer 1

Задание: решить.
($7 frac{1}{4} - 6frac{7}{18}$)*7,2+2,8=9
1) $frac{29}{4} - frac{115}{18}$ = $frac{9*29}{9*4} - frac{2*115}{2*18}$ = $frac{261}{36} - frac{230}{36} = frac{31}{36}$
2) $frac{31}{36} * 7,2 = frac{31}{36} * frac{72}{10} = frac{31*72}{36*10} =$ = $frac{31*2}{1*10} = frac{62}{10}$ = 6,2
3) 6,2+2,8=9