Question

Вычисли удобным способом. 7*(60+2) , 4*(5+5), 23*(3+7),15*(1+20)

Answer 1

7*(60 + 2) = 7*60 + 7 * 2 = 420 + 14 = 434
4 * (5 +5) = 4 * 10 = 40
23 * (3 + 7) = 23 *10 = 230
15 * (1 + 20) = 15 *(1 + 10+10) = 15*1 + 15*10+15*10 = 315