Answer:
24
Explanation:
You want the largest of three numbers that have the ratios 1 : 2 : 3 and have a sum of 48.
Sum
The sum of the ratio units is 1+2+3 = 6. The largest number is 3/6 = 1/2 of the sum:
(1/2) · 48 = 24
The greatest of the three numbers is 24.
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Additional comment
The other two numbers are 8 and 16.