解:51×22+51×77+51等于( 5100 )
∵已知需求出51×22+51×77+51等于多少
A × B + A × C = A × (B + C)
∴51 × 22 + 51 × 77 + 51
= 51 × (22 + 77 + 1)
= 51 × (99 + 1)
= 51 × 100
= 5100
答:51×22+51×77+51等于5100
=57×(22+77+1) =57×100 =5700