99乘以98减98乘以97加96乘以95减95乘以94加.加6乘以5减5乘以4加3乘以2减2乘以1等于多少

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99乘以98减98乘以97加96乘以95减95乘以94加.加6乘以5减5乘以4加3乘以2减2乘以1等于多少

99乘以98减98乘以97加96乘以95减95乘以94加.加6乘以5减5乘以4加3乘以2减2乘以1等于多少
99乘以98减98乘以97加96乘以95减95乘以94加.加6乘以5减5乘以4加3乘以2减2乘以1等于多少

99乘以98减98乘以97加96乘以95减95乘以94加.加6乘以5减5乘以4加3乘以2减2乘以1等于多少
99×98-98×97+96×95-95×94+……+6×5-5×4+3×2-2×1
=98×(99-97)+95×(96-94)+……+5×(6-4)+2(3-1)
=98×2+95×2+……+5×2+2×2
=2×(98+95+92+……+8+5+2)
=2×(2+98)×33/2
=100×33=3300

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