Question

Solve using model or variable.
When thrice a no. is increased by 28, the sum is 172.What is the number?

Answer 1

Ok, So you know that the number was increased by 28. So subtract 28 from 172. You get 144. You also know it was thrice a number. So... divide 144 by 3. You get 48. So 48 is the number. The equation would be (im using "n" for the number) 3n + 28 = 172. :)

Answer 2

Choose a variable to represent the number.
Let x be the number.
Then "thrice a no." is 3x
"thrice a no. is increased by 28" is 3x + 28
"the sum is 172" means 3x + 28 = 172
Solve for x