For this case we have to:
n: Represents the weight of Mary in Kg.
If your sister weighs 15 kg less we have:

Where "y" represents the weight of his sister in kg.
To find how many times Mary is heavier than her sister, we must divide Mary's weight by her sister's weight.
We have then:

Answer:
Mary is
times heavier than her sister.
Answer:
60%
Step-by-step explanation:
Answer: Yes, and she will have 4 cups leftover
Step-by-step explanation:
1 Quart = 4 cups
Convert the quarts: 7 * 4 = 28
Find the amount of cups needed in total: 12* 2 = 24
Subtract to see if possible: 28- 24 = 4
Answer: 
Step-by-step explanation:
For this exercise it is important to remember the following:

Given the following expression:

You can notice that the radicand (the number inside the square root) is negative. Therefore, in order to simplify the expression, you need to follow these steps:
1. Replace
with
and simplify:

2. Descompose 12 into its prime factors:

3. Substitute into the expression:

4. Since
, you can simplify it:
