Question

section b - multiple-choice questions
circle the letter corresponding to your answer. each question is worth 1 mark.

1. \\(-20 \div (-4) + 3 \times (-2)\\) is equal to:

a. \\(-1\\)
b. \\(-11\\)
c. 11
d. 1
e. \\(-4\\)

1. a straight angle is divided into two angles. one angle is three times the size of

the larger angle is:
a. \\(60^\circ\\)
b. \\(120^\circ\\)
c. \\(135^\circ\\)
d. \\(90^\circ\\)
e. \\(45^\circ\\)

1. \\(\frac{3}{5} \div \frac{9}{10}\\) is equal to:

a. \\(\frac{27}{50}\\)
b. \\(\frac{2}{3}\\)
c. \\(\frac{3}{2}\\)
d. \\(\frac{1}{3}\\)
e. \\(\frac{6}{9}\\)

1. \\(0.05 \times 0.8\\) is equal to:

a. 0.4
b. 0.04
c. 4.0
d. 0.004
e. 0.40

1. if \\(20\\%\\) of a number is 36, then the number is:

a. 7.2
b. 180
c. 56
d. 72
e. 144

Explanation:

Evaluate the arithmetic expression

Using the order of operations (BODMAS/PEMDAS), perform division and multiplication from left to right before addition.

$$ -20 \div (-4) = 5 $$

$$ 3 \times (-2) = -6 $$

Combine the results:

$$ 5 + (-6) = -1 $$

Solve the straight angle problem

A straight angle measures \(180^\circ\). Let the smaller angle be \(x\). The larger angle is \(3x\).

$$ x + 3x = 180^\circ \implies 4x = 180^\circ \implies x = 45^\circ $$

The larger angle is:

$$ 3x = 3 \times 45^\circ = 135^\circ $$

Divide the fractions

Using the Fractions and Reciprocal knowledge points:
Using the Reciprocal knowledge point

$$ \frac{3}{5} \div \frac{9}{10} = \frac{3}{5} \times \frac{10}{9} $$

Using the Fractions knowledge point

$$ \frac{3 \times 10}{5 \times 9} = \frac{30}{45} = \frac{2}{3} $$

Multiply the decimals

Multiply the numbers as integers first, then place the decimal point.

$$ 5 \times 8 = 40 $$

Since \(0.05\) has two decimal places and \(0.8\) has one decimal place, the product must have three decimal places:

$$ 0.05 \times 0.8 = 0.040 = 0.04 $$

Solve the percentage equation

Let the unknown number be \(y\). Write the percentage as a fraction or decimal.

$$ 0.20 \times y = 36 $$

Solve for \(y\):

$$ y = \frac{36}{0.20} = \frac{360}{2} = 180 $$

Answer:

Question 1

• A. \(-1\) (Correct answer)
• B. \(-11\)
• C. \(11\)
• D. \(1\)
• E. \(-4\)

Question 2

• A. \(60^\circ\)
• B. \(120^\circ\)
• C. \(135^\circ\) (Correct answer)
• D. \(90^\circ\)
• E. \(45^\circ\)

Question 3

• A. \(\frac{27}{50}\)
• B. \(\frac{2}{3}\) (Correct answer)
• C. \(\frac{3}{2}\)
• D. \(\frac{1}{3}\)
• E. \(\frac{6}{9}\)

Question 4

• A. \(0.4\)
• B. \(0.04\) (Correct answer)
• C. \(4.0\)
• D. \(0.004\)
• E. \(0.40\)

Question 5

• A. \(7.2\)
• B. \(180\) (Correct answer)
• C. \(56\)
• D. \(72\)
• E. \(144\)