Question

6.5×3.7+6.3×6.5

简算：
15.2-6.54-3.46；        2.5+3.7+6.3+6.5；       72×12.5；         8.7×2.5-1.5×8.7．

Answer 1

15.2-6.54-3.46=15.2-（6.54+3.46）=15.2-10=5.22.5+3.7+6.3+6.5=（2.5+6.5）+（3.7+6.3）=9+10=1972×12.5 =9×（8×12.5）=9×100=9008.7×2.5-1.5×8.7=8.7×（2.5-1.5）=8.7×1=8.7