Question

Alex goes to the supermarket every 6 days and Roy goes every 8 days. Alex and Roy both went to the supermarket today. In the next 50 days, how many times will they go to the supermarket together?

• A. 3
• B. 4
• C. 5
• D. 2

Answer 1

The correct option is D 2

Alex and Roy go to the supermarket every 6th and 8th day respectively.
In the next 50 days, they go to the supermarket together will be a common multiple of 6 and 8.
Multiple of 6 = 6, 12, 18, 24, 30, 36, 42, 48, and so on.
Multiple of 8 = 8, 16, 24, 32, 40 48, and so on.
Common multiple of 6 and 8 till 50 = 24, 48
So the common multiple of 6 and 8 less than 50 will be only two.
Therefore they will go to the supermarket together only twice.