10 is a solution.
Step-by-step explanation:
- Step 1: Equation is 60 - (3 × z) = 30 Substitute values of 9, 10, 11 and 12 to find the solution.
When z = 9, 60 - (3 × z) = 60 - (3×9) = 60 - 27 = 33 ≠ 30
When z = 10, 60 - (3 × z) = 60 - (3×10) = 60 - 30 = 30
When z = 11, 60 - (3 × z) = 60 - (3×11) = 60 - 33 = 27 ≠ 30
When z = 12, 60 - (3 × z) = 60 - (3×12) = 60 - 36 = 24 ≠ 30
⇒ 10 is a solution.
