Answer:
- water: 5 packages
- cheese sticks: 3 packages
Explanation:
The number of bottles of water and cheese sticks will be the same when both numbers are equal to the least common multiple (LCM) of 6 and 10, the numbers in each kind of package.
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The LCM can be found by factoring out the greatest common divisor of each of the numbers:
6 = 2 × 3
10 = 2 × 5
The LCM is the product of the unique numbers here: 2 × 3 × 5 = 30.
The number of packages of bottles of water will be 30/6 = 5 packages.
The number of packages of cheese sticks will be 30/10 = 3 packages.
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Additional comment
You may notice that the number of packages of each kind is the unique factor in the other number.