Jarens puppy weighed 3 3/4 ounces at birth. At one week old the puppy weighed 5 1/8 ounces. At two weeks old the puppy weighed 6 1/2 ounces. If the weight of the puppy continues in this pattern, how old will the puppy be at three years old.

So, the puppy gains 1.375 ounces per week.

That’s 7.875 ounces per month and 94.5 ounces per year.

Since there are 16 ounces in 1 pound, divide 94.5 ounces by 16.

That gives you 5.91 pounds per year.

Now, multiply that by 3 years.

The puppy will weigh 17.72 pounds at three years old.