计算:33×34+34×35+35×36+36×37+37×38=_.
问题描述:
计算:33×34+34×35+35×36+36×37+37×38=______.
答
解;33×34+34×35+35×36+36×37+37×38,
=33×(35-1)+34×35+35×36+(35+1)×37+(35+2)×38,
=33×35-33+34×35+35×36+35×37+37+35×38+2×38,
=35×(33+34+36+37+38)-33+37+76,
=35×(200-22)+80,
=7000-770+80,
=6310.