解:5.6×2.1×0.07等于( 1029/1250 ),【即等于0.8232】
∵已知需求出5.6×2.1×0.07等于多少
∴5.6 × 2.1 × 0.07
= (5×10+6)/10 × (2×10+1)/10 × 7/100
= 56/10 × 21/10 × 7/100
= 28/5 × 21/10 × 7/100
= 294/25 × 7/100
= 1029/1250
= 0.8232
答:5.6×2.1×0.07等于1029/1250,【即等于0.8232】