Question

Tính

a) \(\left(-25\right).\left(75-45\right)-75.\left(45-25\right)\)

b) \(\frac{18.12-48.15}{-3.270-3.30}\)

c) \(\frac{2^5.7+2^5}{2^5.5^2-2^5.3}\)

Answer 1

a)  (-25).(75-45)-75.(45-25)=(-25).30-75.20

Answer 2

\(a,\left(-25\right).\left(75-45\right)-75.\left(45-25\right)\)

\(=\left(-25\right).20-75.20\)

\(=20.\left(-25-75\right)\)

\(=20.\left(-100\right)\)

\(=-2000\)

\(b,\frac{18.12-48.15}{-3.270-3.30}\)

\(=\frac{18.12-12.4.15}{-3.270-3.30}\)

\(=\frac{12.\left(18-60\right)}{-3.\left(270+30\right)}\)

\(=\frac{12.\left(-42\right)}{-3.300}\)

\(=\frac{14}{25}\)

\(c,\frac{2^5.7+2^5}{2^5.5^2-2^5.3}\)

\(=\frac{2^5.\left(7+1\right)}{2^5\left(25-3\right)}\)

\(=\frac{2^5.8}{2^5.22}\)

\(=\frac{8}{22}\)

\(=\frac{4}{11}\)