Question

Tính nhanh:

a) 34.15 + 34.85

b) 12.57 + 57.25 + 63.57

c) 36.28 + 36.82 + 64.69 + 64.41

d) 2.31.12 + 4.6.42 + 8.27.3

Answer 1

a) 34.15 + 34.85 = 34.(15+85) = 34.100 = 3400

b) 12.57 + 57.25 + 63.57 = 57.(12+25+63) = 57.100 = 5700

c) 36.28 + 36.82 + 64.69 + 64.41 = 36.(28+82) + 64(69+41) = 36.110 + 64.110 = 110.(36+64) = 11000

d) 2.31.12 + 4.6.42 + 8.27.3 = 24.31 + 24.42 + 24.27 = 24.(31+42+27) = 24.100 = 2400