Answer:
A
Step-by-step explanation:
Let X and Y be the digits.
If a two-digit number is written XY, then its value is 10x+y.
When the digits of the number are interchanged, it's YX, and its value is 10y+x.
The sum of the digits is 12.
The number formed by interchaning the digits is 54 more than the original number.

The digits X and Y are 3 and 9, so the original number is 39.
Answer: 0.8 or 80%
Step-by-step explanation:
First find the total number of marbles:
10 + 15 + 25 = 50 marbles total
To find the number of marbles that are not black:
15 + 25 = 40 marbles that are not black
Set up ratio:
= 0.8 or 80%
Answer:When you multiply a negative number to a positive number, your answer is a negative number. It doesn't matter which order the positive and negative numbers are in that you are multiplying, the answer is always a negative number.
Step-by-step explanation: