Sam is 5 years old. his older brother, tom, is three times as old as sam. when sam is 20, how old will tom be?

Sam is 5
Tom is 3 times older so 3*5=15
The difference between them is 15-5=10 years
When Sam is 20 we add the difference 20+10=30, and we have Tom's age :)

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.

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