1.6.2 Rational Numbers (HOTS Questions), PT3 Practice - Mathematics

1.6.2 Rational Numbers (HOTS Questions), PT3 Practice

Question 5:

Calculate the value of

(- 0.6 \times 1 \frac{1}{4}) - [- 1.6 \times (- 1.5)] \div 0.4

Solution:

\begin{array}{l} (- 0.6 \times 1 \frac{1}{4}) - [- 1.6 \times (- 1.5)] \div 0.4 \\ = ({- 0.6}^{- 0.3} \times \frac{5}{4^{2}}) - [\frac{{- 1.6}^{- 4} \times (- 1.5)}{{0.4}^{1}}] \\ = - \frac{1.5}{2} - 6 \\ = - 0.75 - 6 \\ = - 6.75 \end{array}

Question 6:

Calculate the value of

1 - (- 2 + 7 \times 0.15) \div 2 \frac{1}{2}

Solution:

\begin{array}{l} 1 - (- 2 + 7 \times 0.15) \div 2 \frac{1}{2} \\ = 1 - (- 2 + 1.05) \times \frac{2}{5} \\ = 1 - (- 0.95) \times \frac{2}{5} \\ = 1 - (- 0.38) \\ = 1.38 \end{array}

Question 7:

Calculate the value of

1 \frac{1}{8} \times (\frac{4}{5} - \frac{2}{3})

and express the answer as a fraction in its lowest terms.

Solution:

\begin{array}{l} 1 \frac{1}{8} \times (\frac{4}{5} - \frac{2}{3}) \\ = 1 \frac{1}{8} \times (\frac{12}{15} - \frac{10}{15}) \\ = \frac{9^{3}}{8_{4}} \times \frac{2^{1}}{15_{5}} \\ = \frac{3}{20} \end{array}