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.
Albert Einstein was born in Germany in 1879.He died by refusing surgery.
Answer:
Wait is this melody Montejano from tustin high ?
Answer:
See Below
Step-by-step explanation:
This is very simple, but I can help more if you're stuck.
Take the number of pounds multiplied by the cost per pound.
For example, if I had 5 pounds of peaches, and they are $2 per pound...
5 pounds * $2 per pound = $10
Try it on your own :)