Question

a)-2/5 - 1/3

b) 1/2 . 3/7 + 1/2 . 4/7

c) 5/4 + 9 : 3/2 - 2/3 . (-3)^2

Answer 1

a) \(-\dfrac{2}{5}-\dfrac{1}{3}=\dfrac{-6}{15}-\dfrac{5}{15}=\dfrac{-11}{15}\)

b) \(\dfrac{1}{2}\cdot\dfrac{3}{7}+\dfrac{1}{2}\cdot\dfrac{4}{7}=\dfrac{1}{2}\cdot\left(\dfrac{3}{7}+\dfrac{4}{7}\right)=\dfrac{1}{2}\cdot1=\dfrac{1}{2}\)

c) \(\dfrac{5}{4}+9:\dfrac{3}{2}-\dfrac{2}{3}\cdot\left(-3\right)^2=\dfrac{5}{4}+9\cdot\dfrac{2}{3}-\dfrac{2}{3}\cdot9=\dfrac{5}{4}+0=\dfrac{5}{4}\)