Mathematics Flashcards

A student earns $12.50 per hour and works 34 hours in a week. Which expression correctly calculates total earnings?

Answer: 12.50 × 34

Total earnings = rate × hours = 12.50 × 34 = $425.00.

What is the value of 3² + 4²?

Answer: 25

3² = 9 and 4² = 16, so 9 + 16 = 25.

A rectangle has a length of 15 cm and a width of 8 cm. What is its perimeter?

Answer: 46 cm

Perimeter = 2(l + w) = 2(15 + 8) = 2(23) = 46 cm.

Which of the following is equivalent to 0.75?

Answer: 3/4

0.75 = 75/100 = 3/4 when reduced to lowest terms.

If 5x − 3 = 22, what is x?

Answer: 5

5x = 22 + 3 = 25, so x = 25 ÷ 5 = 5.

A triangle has angles measuring 55° and 80°. What is the measure of the third angle?

Answer: 45°

The three angles of a triangle sum to 180°, so the third angle = 180 − 55 − 80 = 45°.

Which number is NOT a prime number?

Answer: 51

51 = 3 × 17, so it has factors other than 1 and itself and is not prime.

A recipe requires 2¼ cups of flour. If you want to make 1.5 times the recipe, how many cups do you need?

Answer: 3⅜ cups

2¼ = 2.25; 2.25 × 1.5 = 3.375 = 3⅜ cups.

Which of the following represents 4.2 × 10³ in standard notation?

Answer: 4,200

10³ = 1,000, so 4.2 × 1,000 = 4,200.

The mean of five test scores is 78. Four of the scores are 70, 82, 75, and 85. What is the fifth score?

Answer: 78

Sum = 78 × 5 = 390; fifth score = 390 − (70+82+75+85) = 390 − 312 = 78.

A cylinder has a radius of 3 cm and a height of 10 cm. What is its volume? (Use π ≈ 3.14)

Answer: 282.6 cm³

V = πr²h = 3.14 × 9 × 10 = 282.6 cm³.

Which of the following is equivalent to (−2)³?

Answer: −8

(−2)³ = (−2) × (−2) × (−2) = 4 × (−2) = −8.

A line passes through the points (0, 3) and (2, 7). What is its slope?

Answer: 2

Slope = (7−3)/(2−0) = 4/2 = 2.

Which measure of central tendency is most affected by an outlier in a data set?

Answer: Mean

The mean is calculated using all values, so a very high or low outlier significantly shifts it.