Question

用简便方法计算（用等式计算）

1.23456+34562+45623+56234+62345
2.45678+56784+67845+78456+84567
3.124.68+324.68+524.68+724.68+924.68

Answer 1

23456+34562+45623+56234+62345
=(2+3+4+5+6)*11111=222220

45678+56784+67845+78456+84567
=(4+5+6+7+8)*11111=333330

124.68+324.68+524.68+724.68+924.68
=(1+3+5+7+9)*100+24.68*5
=2500+123.4
=2623.4

Answer 2

124.68+324.68+524.68+724.68+924.68
＝124+324+524+724+924+0.68*5
＝【100+900】+【300+700 】+500+24*5+3.4
＝1000+1000+500+120+3.4
＝2500+120+3.4
＝2620+3.4
＝2623.4