题目
计算。
①7.36-(1.25+0.35)
②45×( + )
③ ÷ ×
④8×4×1.25×2.5
⑤806×99+806
⑥36×[1+( + )]
答案:①7.36-(1.25+0.35) =7.36-1.6 =5.76 ②45×( 59 + 29 ) =45×59+45×29 =25+10 =35 ③ 13 ÷ 25 × 715 =13×52× 715 = 718 ④8×4×1.25×2.5 =(8×1.25)×(4×2.5) =10×10 =100 ⑤806×99+806 =806×(99+1) =806×100 =80600 ⑥36×[1+( 23 + 12 )] =36×1+36×23+36×12 =36+24+18 =60+18 =78