Question

用简便方法计算下列各题。

54*51/43+51*19/43=？ 19.98*37-199.8*1.9+1998*0.82=？
0.25*1.25*320=？ 0.32*6.7+3.2*0.43-0.32=？
请用简便方法计算，越详细越好。谢谢！
第一道简便计算的算式正确的式子是24*51/43+51*19/43=?

Answer 1

24*51/43+51*19/43
=51*(24+19)/43
=51*43/43
=51

19.98*37-199.8*1.9+1998*0.82
=1998*0.37-1998*0.19+1998*0.82
=1998*(0.37-0.19+0.82)
=1998*1
=1998

0.25*1.25*320
=0.25*1.25*4*8*10
=0.25*4 *1.25*8 *10
=1*10*10
=100

0.32*6.7+3.2*0.43-0.32
=0.32*6.7+0.32*4.3-0.32*1
=0.32*(6.7+4.3-1)
=0.32*10
=3.2