Answer:
Step-by-step explanation:
Let p represent cost of each drink.
We have been given that the medium pizza costs two times as much as one drink, so the cost of medium pizza would be 
.
We are also told that the large pizza costs three times as much as one drink, so the cost of la pizza would be 
.
We have been given that Mary wants to buy one large pizza, one medium pizza, and three drinks.
Since the cost of one drink is p, so cost of 3 three drinks would be .
The total cost of one large pizza, one medium pizza, and three drinks would be 
Mary started with $30, so amount left after all of her purchases would be 30 minus total cost of all purchases.
Therefore, Mary will have dollars left after making all of her purchases.
Step-by-step explanation:
Water is the universal solvent" with a grain of salt (pun intended). Of course it cannot dissolve everything, but it does dissolve more substances than any other liquid, so the term fits pretty well. Water's solvent properties affect all life on Earth, so water is universally important to all of us.
Answer:
Before anyone gives anyone money, Mario has 24 dollars and Roberto has 12 dollars. After they give each other money, both of them have 18 dollars.
Step-by-step explanation:
Mario has twice as much as Roberto, BUT if Mario gives Roberto 6 dollars, then they have the same amount.
M = 2R
M - 6 = R + 6
To isolate M, you need to add 6 on both sides.
M - 6 + 6 = R + 6 + 6
M = R + 12
M = 2R
Substitute M for the value above that we found.
R + 12 = 2R
Now we subtract R on both sides, so that only one side has the variable R.
R - R + 12 = 2R - R
12 = R
M = 2R
Substitute for the value of R.
M = 2 x 12
M = 24
The answer to this problem is 1 :)
