Brian chooses an integer, multiplies it by 4 then subtracts 30. He then multiplies his answer by 2 and finally subtracts 10. His answer is a two-digit number.
What is the largest integer he could choose?
Select one option, then click Submit.
10
15
18
20
21
Select an option, then submit.
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Junior Kangaroo 2015 (2015)
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