Exercise: Foundational Math
Questions for: Arithmetical Simplification
A student is evaluating a complex numerical expression involving multiple operations. To find the correct answer, the student must apply the order of operations accurately.
What is the simplified value of the expression `5 * (18 - 3^2) + 24 / 6`?
A: 49
B: 64
C: 85
D: 65
Answer: A
The expression is `5 * (18 - 3^2) + 24 / 6`.
1. First, evaluate the exponent inside the parentheses: `3^2 = 9`.
The expression becomes `5 * (18 - 9) + 24 / 6`.
2. Next, complete the operation inside the parentheses: `18 - 9 = 9`.
The expression becomes `5 * 9 + 24 / 6`.
3. Perform multiplication and division from left to right:
`5 * 9 = 45`.
`24 / 6 = 4`.
The expression becomes `45 + 4`.
4. Finally, perform the addition: `45 + 4 = 49`.
The simplified value of the expression is 49.
Why others are wrong:
A โ Correct answer.
B โ This result occurs if `3^2` is incorrectly calculated as `3 * 2 = 6` instead of `3 * 3 = 9`.
C โ This result occurs if multiplication `5 * 18` is performed before simplifying the parentheses `(18 - 3^2)`, violating the order of operations.
D โ This result occurs if the student incorrectly groups operations by first evaluating `(18 - 3^2) + 24 / 6` and then multiplying the entire sum by `5`.
A manager is calculating the final balance of a project budget. The initial budget was 50 units. Expenses included three items costing 8 units each and another expense of 24 units divided among 4 sub-projects. Additionally, a bonus of 2 cubed units was added.
What is the final simplified balance?
A: 26
B: 28
C: 34
D: What is the final simplified balance?
A. 26
B. 28
C. 34
D. 40
Answer: B
The expression to simplify is: 50 - (3 * 8 + 24 / 4) + 2^3
1. **Exponents first:** Calculate 2^3 = 8.
The expression becomes: 50 - (3 * 8 + 24 / 4) + 8
2. **Parentheses next:** Inside the parentheses, perform multiplication and division from left to right.
Calculate 3 * 8 = 24.
Calculate 24 / 4 = 6.
The expression inside parentheses becomes: 24 + 6 = 30.
The overall expression is now: 50 - 30 + 8
3. **Addition and Subtraction last:** Perform these operations from left to right.
Calculate 50 - 30 = 20.
Calculate 20 + 8 = 28.
The final simplified balance is 28.
Why others are wrong:
A โ This result would be obtained if 2^3 was incorrectly calculated as 2*3=6.
B โ This is the correct answer.
C โ This result would be obtained if addition was performed before multiplication/division inside the parentheses (e.g., 3 * (8 + 24) / 4).
D โ This result would be obtained if the parentheses were largely ignored, and operations were performed mostly left-to-right after exponents, but still respecting multiplication/division over addition/subtraction.
Discuss About this Question.
A technician is performing calculations for a circuit design.
Simplify the following expression:
24 รท 3 ร (7 - 2)ยฒ - 10
A: 190
B: 350
C: 70
D: 30
Answer: A
1. Parentheses: First, evaluate the expression inside the parentheses: (7 - 2) = 5.
The expression becomes 24 รท 3 ร (5)ยฒ - 10.
2. Exponents: Next, evaluate the exponent: (5)ยฒ = 25.
The expression becomes 24 รท 3 ร 25 - 10.
3. Multiplication and Division (from left to right):
Perform the division: 24 รท 3 = 8.
The expression becomes 8 ร 25 - 10.
Perform the multiplication: 8 ร 25 = 200.
The expression becomes 200 - 10.
4. Addition and Subtraction (from left to right):
Finally, perform the subtraction: 200 - 10 = 190.
Why others are wrong:
B โ This result (350) occurs if the exponent `(7-2)ยฒ` is incorrectly calculated as `7ยฒ - 2ยฒ = 49 - 4 = 45`, leading to `24 รท 3 ร 45 - 10 = 8 ร 45 - 10 = 360 - 10 = 350`.
C โ This result (70) occurs if the exponent `(7-2)ยฒ` is incorrectly calculated as `(7-2) ร 2 = 5 ร 2 = 10`, leading to `24 รท 3 ร 10 - 10 = 8 ร 10 - 10 = 80 - 10 = 70`.
D โ This result (30) occurs if the exponent `( )ยฒ` is omitted entirely or treated as `(7-2) = 5` instead of `5ยฒ`, leading to `24 รท 3 ร 5 - 10 = 8 ร 5 - 10 = 40 - 10 = 30`.
Discuss About this Question.
A project manager is reviewing a team's progress and needs to calculate a specific performance metric. This metric is derived from simplifying the following arithmetic expression: `36 รท 3 + 4 ร (15 - 8) - 2^3`.
What is the simplified value of the expression?
A: 34
B: 104
C: This metric is derived from simplifying the following arithmetic expression: `36 รท 3 + 4 ร (15 - 8) - 2^3`.
What is the simplified value of the expression?
A. 34
B. 104
C. 28
D: 32
Answer: D
Apply the order of operations (PEMDAS/BODMAS): Parentheses/Brackets, Exponents/Orders, Multiplication and Division (from left to right), Addition and Subtraction (from left to right).
1. **Parentheses/Brackets:** `(15 - 8) = 7`
The expression becomes: `36 รท 3 + 4 ร 7 - 2^3`
2. **Exponents/Orders:** `2^3 = 2 ร 2 ร 2 = 8`
The expression becomes: `36 รท 3 + 4 ร 7 - 8`
3. **Multiplication and Division (from left to right):**
`36 รท 3 = 12`
`4 ร 7 = 28`
The expression becomes: `12 + 28 - 8`
4. **Addition and Subtraction (from left to right):**
`12 + 28 = 40`
`40 - 8 = 32`
The simplified value is 32.
Why others are wrong:
A โ This result occurs if `2^3` is incorrectly calculated as `2 ร 3 = 6`, leading to `12 + 28 - 6 = 34`.
B โ This result occurs if operations are performed strictly from left to right without adhering to BODMAS/PEMDAS (e.g., performing `12 + 4` before `4 ร 7`), leading to `(12 + 4) ร 7 - 8 = 16 ร 7 - 8 = 112 - 8 = 104`.
C โ This result occurs if `(15 - 8)` is mistakenly calculated as `6` instead of `7`, leading to `36 รท 3 + 4 ร 6 - 2^3 = 12 + 24 - 8 = 36 - 8 = 28`.
D โ This is the correct answer.
Discuss About this Question.
A student is reviewing order of operations. They encounter a multi-step expression and need to find its simplified value to ensure their understanding.
What is the simplified value of the expression: (18 รท 3 + 2) ร 4 - 10?
A: 4
B: 22
C: 26
D: 30
Answer: B
1. First, simplify the division within the parentheses: 18 รท 3 = 6.
2. Next, simplify the addition within the parentheses: 6 + 2 = 8.
3. Then, perform the multiplication: 8 ร 4 = 32.
4. Finally, perform the subtraction: 32 - 10 = 22.
Why others are wrong:
A โ This results from incorrectly ignoring the parentheses and performing operations from left to right (18 รท 3 + 2 ร 4 - 10 = 6 + 8 - 10 = 4).
C โ This results from a calculation error where 8 ร 4 is incorrectly evaluated as 36 instead of 32 (36 - 10 = 26).
D โ This results from a calculation error where 32 - 10 is incorrectly evaluated as 30.
Discuss About this Question.
Ad Slot (Above Pagination)
Discuss About this Question.