作业帮出几道脱式计算题(1) 1/3+3/4+2/5+5/7+9/20+10/21+11/24+19/35 (2) 51/2/3×3/5+71/3/4×4/7+91/4/5÷9/5 (3) 若a△b=a/b-b/a,试求[2△(5△3)]+8/15的值.
来源：学生作业帮助网 编辑：作业帮 时间：2024/04/30 11:52:53
![出几道脱式计算题(1) 1/3+3/4+2/5+5/7+9/20+10/21+11/24+19/35 (2) 51/2/3×3/5+71/3/4×4/7+91/4/5÷9/5 (3) 若a△b=a/b-b/a,试求[2△(5△3)]+8/15的值.](/uploads/image/z/2515775-23-5.jpg?t=%E5%87%BA%E5%87%A0%E9%81%93%E8%84%B1%E5%BC%8F%E8%AE%A1%E7%AE%97%E9%A2%98%281%29+1%2F3%2B3%2F4%2B2%2F5%2B5%2F7%2B9%2F20%2B10%2F21%2B11%2F24%2B19%2F35+%282%29+51%2F2%2F3%C3%973%2F5%2B71%2F3%2F4%C3%974%2F7%2B91%2F4%2F5%C3%B79%2F5+%283%29+%E8%8B%A5a%E2%96%B3b%3Da%2Fb-b%2Fa%2C%E8%AF%95%E6%B1%82%5B2%E2%96%B3%285%E2%96%B33%29%5D%2B8%2F15%E7%9A%84%E5%80%BC.)
出几道脱式计算题(1) 1/3+3/4+2/5+5/7+9/20+10/21+11/24+19/35 (2) 51/2/3×3/5+71/3/4×4/7+91/4/5÷9/5 (3) 若a△b=a/b-b/a,试求[2△(5△3)]+8/15的值.
出几道脱式计算题
(1) 1/3+3/4+2/5+5/7+9/20+10/21+11/24+19/35
(2) 51/2/3×3/5+71/3/4×4/7+91/4/5÷9/5
(3) 若a△b=a/b-b/a,试求[2△(5△3)]+8/15的值.
出几道脱式计算题(1) 1/3+3/4+2/5+5/7+9/20+10/21+11/24+19/35 (2) 51/2/3×3/5+71/3/4×4/7+91/4/5÷9/5 (3) 若a△b=a/b-b/a,试求[2△(5△3)]+8/15的值.
1.
1/3+3/4+2/5+5/7+7/8+9/20+10/21+11/24+19/35
=1/3+3/4+2/5+5/7+7/8+(4/20+5/20)+(3/21+7/21)+ (3/24+8/24)+(5/35+14/35)
=1/3+3/4+2/5+5/7+7/8+1/5+1/4+1/7+1/3+1/8+1/3+2/5+1/7
=1/3*3+(3/4+1/4)+(2/5+1/5+2/5)+(5/7+1/7+1/7)+(7/8+1/8)
=1+1+1+1+1
=5
2.
(51+2/3)÷(5/3)+(71+3/4)÷(7/4)+(91+4/5)÷(9/5)
=(50+5/3)*(3/5)+(70+7/4)*(4/7)+(90+9/5)*(5/9)
=50*3/5+（5/3)(3/5)+70*4/7+(7/4)*(4/7)+90*5/9+(9/5)*(5/9)
=30+1+40+1+50+1
=123