(222-22):2=100
222-22=200 и разделить на 2 100
253-153+100
1)253-153=100
2)100+100=200
Ответ:200
А) 3/7 * (1/4 + 4/9) = 25/84
1) 1/4 + 4/9 = 9/36 + 16/36 = 25/36
2) 3/7 * 25/36 = (1*25)/(7*12) = 25/84
б) 4/5 - 1/4 : 5/6 = 5/10 = 0,5
1) 1/4 : 5/6 = 1/4 * 6/5 = (1*3)/(2*5) = 3/10
2) 4/5 - 3/10 = 8/10 - 3/10 = 5/10