3/1*2+3/2*3+3/3*4+……+3/99*100.如果写出以下两题,5/6+11/12+19/20+29/30+41/42=?(9又2/7+7又2/9)÷(5/7+5/9)=?
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![3/1*2+3/2*3+3/3*4+……+3/99*100.如果写出以下两题,5/6+11/12+19/20+29/30+41/42=?(9又2/7+7又2/9)÷(5/7+5/9)=?](/uploads/image/z/223250-50-0.jpg?t=3%2F1%2A2%2B3%2F2%2A3%2B3%2F3%2A4%2B%E2%80%A6%E2%80%A6%2B3%2F99%2A100.%E5%A6%82%E6%9E%9C%E5%86%99%E5%87%BA%E4%BB%A5%E4%B8%8B%E4%B8%A4%E9%A2%98%2C5%2F6%2B11%2F12%2B19%2F20%2B29%2F30%2B41%2F42%3D%3F%EF%BC%889%E5%8F%882%2F7%2B7%E5%8F%882%2F9%EF%BC%89%C3%B7%EF%BC%885%2F7%2B5%2F9%EF%BC%89%3D%3F)
3/1*2+3/2*3+3/3*4+……+3/99*100.如果写出以下两题,5/6+11/12+19/20+29/30+41/42=?(9又2/7+7又2/9)÷(5/7+5/9)=?
3/1*2+3/2*3+3/3*4+……+3/99*100.
如果写出以下两题,
5/6+11/12+19/20+29/30+41/42=?
(9又2/7+7又2/9)÷(5/7+5/9)=?
3/1*2+3/2*3+3/3*4+……+3/99*100.如果写出以下两题,5/6+11/12+19/20+29/30+41/42=?(9又2/7+7又2/9)÷(5/7+5/9)=?
1、原式=3×(1-1/2+1/2-1/3+……+1/99-1/100)=3×(1-1/100)=2.97
2、原式=1-1/6+1-1/12+1-1/20+1-1/30+1-1/42=5-(1/2-1/3+1/3-1/4+……+1/6-1/7)=4又9/14
3、原式=13
原式=3×(1-1/2+1/2-1/3+……+1/99-1/100)=3×(1-1/100)=297/100
原式=1-1/6+1-1/12+1-1/20+1-1/30+1-1/42=5-(1/2-1/3+1/3-1/4+……+1/6-1/7)=65/70
原式=(65/7+65/9)÷5÷(1/7+1/9)= 65*(1/7+1/9)÷5÷(1/7+1/9)= 13
3/1*2+3/2*3+3/3*4+……+3/99*100
=3*[1/(1*2)+1/(2*3)+……+1/(99*100)
=3*[1-1/2+1/2-1/3+1/3-1/4+……+1/99-1/100]
=3*[1-1/100]
=3*99/100
=297/100
5/6+11/12+19/20+29/30+41/42
=[1-1...
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3/1*2+3/2*3+3/3*4+……+3/99*100
=3*[1/(1*2)+1/(2*3)+……+1/(99*100)
=3*[1-1/2+1/2-1/3+1/3-1/4+……+1/99-1/100]
=3*[1-1/100]
=3*99/100
=297/100
5/6+11/12+19/20+29/30+41/42
=[1-1/6+1-1/12+1-1/20+1-1/30+1-1/42]
=5-[1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7]
=5-[1/2-1/7]
=5-5/14
=4又9/14
(9又2/7+7又2/9)÷(5/7+5/9)
=(9+7+2/7+2/9)/(80/63)
=(16+32/63)*63/80
=63/5+2/5
=13 .
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