Question

Вычислите рациональным способом: 1) 23,4273×5+76,5727×5+6,346= 2) 45,3×0,5×2+0,25×5,7×4= 3)1,21+4.68-121:100-54756:10000 4) 123,45×6,789-678,9×1,2345

Answer 1

1) 23,4273×5+76,5727×5+6,346= (23,4273+76,5727)×5+6,346=100*5+6,346=506,346

2) 45,3×0,5×2+0,25×5,7×4= 45,3×(0,5×2)+(0,25×4)*5,7=45,3+5,7=51

3)1,21+4.68-(121:100)-(54756:10000)=1,21-1,21+4,68-5,4756=-0,7956

4) 123,45×6,789-678,9×1,2345=1,2345*100*6,789-6,789*100*1,2345=0

Answer 2

1) 5*(23,4273+76,5727)+6,346= 5*100+6,346=500+6,346=506,346;
2) 45,3*(0,5*2)+5,7*(0,25*4)=45,3*1+5,7*1=45+(0,3+5,7)=45+6=51;
3) 1,21+4,68-1,21-5,4756=4+0,6800-5-0,4756=-1+0,2044=-0,7956;
4) 12345*10^(-2)*6789*10^(-3) - 6789*10^(-1)*12345*10^(-4)= 12345*6789*10^(-5)-6789*12345*10^(-5)=0

Answer 3

1) 23.4273 × 5 + 76.5727 × 5 + 6.346 = 117.1365 + 382.8635 + 6.346 = 506.346

2) 45.3 × 0.5 × 2 + 0.25 × 5.7 × 4 = 45.3 × 1 × 2 + 0.25 × 22.8 = 90.6 + 5.7 = 96.3

3) 1.21 + 4.68 - 121 ÷ 100 - 54756 ÷ 10000 = 1.21 + 4.68 - 1.21 - 5.4756 = 5.89 - 6.6856 = -0.7956

4) 123.45 × 6.789 - 678.9 × 1.2345 = 838.5005 - 837.70405 = 0.79645