Question

[Nguyễn Trần Kim Khánh]

Rút gọn các phân số sau

a) 484/-860

b) 14.20-70.13/21.10+7.80

c) -10.21.35/15.(-14).(-4)

d) (-4)^3.27^2.(-10)^3/8^3.(-9)^2.25^2

Answer 1

[Nguyễn Thu Trang]

a)\(\frac{484}{-860}=\frac{121}{215}\)

b)\(\frac{14.20-70.13}{21.10+7.80}=\frac{7.2.10.2-7.10.13}{7.3.10+7.8.10}=\frac{7.4.10-7.10.13}{7.3.10+7.8.10}=\frac{7.10.\left(4-13\right)}{7.10.\left(3+8\right)}=\frac{-9}{11}\)

c)\(\frac{-10.21.35}{15.\left(-14\right).\left(-4\right)}=\frac{-2.5.3.7.7.5}{3.5.7.\left(-2\right).\left(-4\right)}=\frac{35}{-4}\)

d)\(\frac{\left(-4\right)^3.27^2.\left(-10\right)^3}{8^3.\left(-9\right)^2.25^2}=\frac{\left(-2^2\right)^3.\left(3^3\right)^2.\left(-2.5\right)^3}{\left(2^3\right)^3.\left[\left(-3\right)^2\right]^2.\left(5^2\right)^2}=\frac{-2^5.3^5.\left(-2\right)^3.5^3}{2^6.\left(-3\right)^4.5^4}=\frac{2^2.3}{5}=\frac{4.3}{5}=\frac{12}{5}\)

Answer 2

[Đỗ Việt Nhật]

a,\(\frac{484}{-860}=\frac{484:\left(-4\right)}{-860:\left(-4\right)}=\frac{-121}{215}\)

b,\(\frac{14.20-70.13}{21.10+7.80}\)\(=\frac{280-910}{210+560}=\frac{-630}{770}=\frac{-9}{11}\)

c,\(\frac{-10.21.35}{15.\left(-14\right).\left(-4\right)}=\frac{1.\left(-3\right).35}{3.2.2}=\frac{105}{12}=8\frac{3}{4}\)

d,tự làm