Expressions & Order of Operations — Practice
A letter stands for a number you have not been told yet, and the order of operations settles what a written expression means.
What these questions cover
These questions use 1 idea from the course. Follow any of them for a definition, where it is taught, and what it leads to.
- Exponent — How many times the base is used as a factor. In 53 the exponent is 3.
Problem 1
Work out 2 + 3 × 4.
Worked answer
14
3 × 4 = 12
2+12 = 14
Problem 2
Work out (2 + 3) × 4.
Worked answer
20
5 × 4 = 20
Problem 3
Work out 53.
Worked answer
125
5 × 5 × 5 = 125
Problem 4
Work out 24.
Worked answer
16
2 × 2 × 2 × 2 = 16
Problem 5
Find the value of 5n + 2 when n = 7.
Worked answer
37
35 + 2 = 37
Problem 6
Work out 2 + 3 × 42.
Worked answer
50
42 = 16
3 × 16 = 48
+2 = 50
Problem 7
Work out 12 ÷ 3 × 2.
Worked answer
8
12 ÷ 3 = 4
4 × 2 = 8
Problem 8
Work out 20 - 4 × 3 + 1.
Worked answer
9
20-12+1 = 9
Problem 9
A taxi charges $3 plus $2 a mile. Write the cost for m miles.
Worked answer
2m+3
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Problem 10
A club charges $5 each plus a $2 fee. Write the cost for n people.
Worked answer
5n+2
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Problem 11
Find the value of 4n2 - 5 when n = 3.
Worked answer
31
32 = 9
4 × 9 = 36
-5 = 31
Problem 12
Find the value of 3n2 when n = -2.
Worked answer
12
(-2)2 = 4
3 × 4 = 12
Problem 13
Expand 3(x + 4).
Worked answer
3x+12
3x + 12
Problem 14
Simplify 4x + 3x.
Worked answer
7x
7x
Problem 15
Which expression is equivalent to 2(n+5)?
- 2n+10
- 2n+5
- n+10
- 2n+7
Worked answer
2n+10
2n + 10
Problem 16
Find the value of a+b2 when a = 7 and b = 11.
Worked answer
9
182 = 9