Write variable equations: word problems
Key Notes :
✈️ A variable is a letter that represents an unknown number.
Learn with an example
🎯 A primary school has 84 students. Each class has 12 students. Which equation, when solved, will tell how many classes the school has?
- c ÷ 84 = 12
- 84 − c = 12
- 84 ÷ c = 12
- c − 12 = 84
- You can use the variable c to represent the number of classes.
- 84 = total number of students
c = number of classes
12 = number of students in each class - This is the correct equation:
- (total number of students) ÷ (number of classes) = number of students in each class
- 84 ÷ c = 12
🎯 Kenji got out all of his yellow blocks. He mixed them together with his 12 green blocks and counted 67 blocks in all. Which equation, when solved, will show how many yellow blocks Kenji has?
- y + 67 = 12
- 12 × y = 6
- 7y − 12 = 67
- y + 12 = 67
- You can use the variable y to represent the number of yellow blocks.
- 67 = total number of blocks
12 = number of green blocks
y = number of yellow blocks - This is the correct equation:
- (number of yellow blocks) + (number of green blocks) = total number of blocks
- y + 12 = 67
🎯 The books at the library are split among 14 shelves. There are 6 books on each shelf. Which equation, when solved, will tell how many books are in the library?
- 14 × b = 6
- 14 ÷ 6 = b
- b × 14 = 6
- b ÷ 14 = 6
- You can use the variable b to represent the total number of books.
- b = total number of books
6 = number of books per shelf
14 = number of shelves - This is the correct equation:
- (total number of books) ÷ (number of shelves) = number of books per shelf
- b ÷ 14 = 6
Let’s practice!🖊️
