West B Math: Number Sense and Operations Questions and Answers

Question 1

A retail item is originally priced at $80.00. It is first discounted by 20%, and then a coupon is applied for an additional 10% off the discounted price. What is the final price of the item?

Accepted Answer

$57.60

Answer

First, calculate the initial 20% discount: $80.00 * 0.20 = $16.00. The sale price is $80.00 - $16.00 = $64.00. Next, calculate the additional 10% coupon on the sale price: $64.00 * 0.10 = $6.40. The final price is $64.00 - $6.40 = $57.60.

Question 2

Which of the following lists correctly orders the numbers from least to greatest?

Accepted Answer

0.35, 3/8, 38%, 2/5

Answer

To compare the numbers, convert them all to decimals: 3/8 = 0.375, 0.35 remains 0.35, 38% = 0.38, and 2/5 = 0.40. Ordering these decimals from least to greatest gives 0.35, 0.375, 0.38, 0.40, which corresponds to the original numbers in the order 0.35, 3/8, 38%, 2/5.

Question 3

What is the value of the expression 5 + 3 * (12 - 4 * 2)² ?

Accepted Answer

53

Answer

Following the order of operations (PEMDAS/BODMAS): First, solve inside the Parentheses: 4 * 2 = 8, then 12 - 8 = 4. Next, handle the Exponent: 4² = 16. Then, perform the Multiplication: 3 * 16 = 48. Finally, do the Addition: 5 + 48 = 53.

Question 4

A map has a scale where 1.5 inches represents 40 miles. If the distance between two cities on the map is 5.25 inches, what is the actual distance between the cities in miles?

Accepted Answer

140 miles

Answer

This can be solved by setting up a proportion: (1.5 inches / 40 miles) = (5.25 inches / x miles). Cross-multiply to solve for x: 1.5 * x = 5.25 * 40. This gives 1.5x = 210. Dividing both sides by 1.5 yields x = 140 miles.

Question 5

The diameter of a specific virus is approximately 0.00000008 meters. How would this number be expressed in scientific notation?

Accepted Answer

8 x 10⁻⁸ m

Answer

To write 0.00000008 in scientific notation, move the decimal point to the right until there is one non-zero digit to its left. In this case, the decimal moves 8 places to the right to get '8'. Because the original number is less than 1, the exponent is negative. Therefore, the correct notation is 8 x 10⁻⁸ m.

West B Test Practice Test

West B Test Practice Test

West B Math: Number Sense and Operations Questions and Answers