1/1*4+1/4*7+1/7*10+10*13+.+1/94*97+1/97*100简算
问题描述:
1/1*4+1/4*7+1/7*10+10*13+.+1/94*97+1/97*100简算
答
1/1*4+1/4*7+1/7*10+10*13+....+1/94*97+1/97*100
=1/3(1-1/4)+1/3(1/4-1/7)+1/3(1/7-1/10)+......+1/3(1/94-1/97)+1/3(1/97-1/100)
=1/3(1-1/100)
=33/100
答
1/1*4+1/4*7+1/7*10+1/10*13+....+1/94*97+1/97*100
=1/3 [(1-1/4) +(1/4-1/7)+(1/7-1/10)+....+(1/97-1/100) ]
=1/3(1-1/100)
=33/100
答
1/1*4+1/4*7+1/7*10+10*13+.+1/94*97+1/97*100
=1/3*(1-1/4+1/4-1/7+1/7-1/10+...+1/97-1/100)
=1/3*(1-1/100)
=1/3*99/100
=33/100
答
原式
=(1-1/4+1/4-1/7+1/7-1/10+……+1/94-1/97+1/97-1/100)/3
=33/100