设M=10.9+21.81+32.72+43.63+54.54+65.45+76.36+87.27+98.18+9.09,那么M的百分位上的数字是 _ ,M的各位数字之和是 _ .

问题描述:

设M=10.9+21.81+32.72+43.63+54.54+65.45+76.36+87.27+98.18+9.09,那么M的百分位上的数字是 ___ ,M的各位数字之和是 ___ .

M=10.9+21.81+32.72+43.63+54.54+65.45+76.36+87.27+98.18+9.09
=(10.9+65.45)+(21.81+9.09)+(32.72+98.18)+(43.63+87.27)+(54.54++76.36)
=76.35+30.9+130.9+130.9+130.9
=107.25+130.9×3
=107.25+392.7
=499.95;
故答案为:5,499.95.