Math · Age 11 · Algebra
Algebraic Expressions & Formulas (Ex. 3)
Write and use formulas to solve problems in context.
Module
Algebra
Age
Age 11
Duration
10 min
Questions
5
What's in this exercise
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Question 1
Multiple choice
The perimeter of a square with side s is P = 4s. What is the perimeter when s = 7?
Question 2
Multiple choice
A formula for the cost of a phone plan is C = 10 + 0.05n, where n is the number of texts. What is the cost for 200 texts?
Question 3
Multiple choice
The formula for speed is S = D/T. If distance D = 120 km and time T = 3 h, what is the speed?
Question 4
Sequence
Use the formula A = l × w to find the area. l = 12, w = 7. A = 12 × 7 = ___.
Question 5
True or false
In the formula V = lwh, if l = 3, w = 4, and h = 5, then V = 60.