Unit 2 · Number Theory

Multiples Under 50 — Largest Minus Smallest

Lesson 3 of 18

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About this lesson

Kim’s multiples of 5 (0–50): largest = 45. Jamie’s even multiples of 7 (0–50): 14, 28, 42 — smallest = 14. Difference = 45 − 14 = 31.

Chapters

0:00Introduction
0:22The Question
0:58Finding Kim's Largest Number
1:24Finding Jamie's Smallest Number
1:56Calculating the Target Difference
2:17Exam Strategy — The Constraint Checklist
2:51Confirming the Final Option

Question

Kim and Jamie each think of a different whole number that is greater than zero and less than 50.

Kim’s number is a multiple of 5.

Jamie’s number is an even number which is a multiple of 7.

What is the difference between the largest possible value of Kim’s number and the smallest possible value of Jamie’s number?

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