Question

1.25+2.25+3.25+4.25…+50.25的简便方法？

Answer 1

1.25+2.2.+3.25+4.25+……+50.25
＝1+2+3+4+……+50+0.25×50
＝（1+50）×25+12.5
＝51×25+12.5
＝1275+12.5
＝1287.5

Answer 2

把后面的小数拆分出来，前面整数就是一个标准的等差数列了，直接套用公式就可以了
(1+50)×50/2+0.25×50
=1275+12.5
=1287.5

Answer 3

1.25＋2.25＋3.25＋4.25…＋50.25
＝（1.25＋50.25）×50÷2
＝51.5×50÷2
＝1287.5

Answer 4

1+2+3+…+50会算吗？再加上50个0.25就行了

Answer 5

1.25+2.25+3.25+4.25+…+50.25
=1+2+3+4+…+50+0.25+0.25+0.25+…+0.25(50个0.25)
=(1+50)×50÷2+50×0.25
=1275+12.5
=1287.5
或原式=(1.25+50.25)×50÷2
=51.5×25
=1287.5