<u>Answer</u>:
x = 7, y = 2
<u>Explanation</u>:
equations given:
x + 7y = 21
x + 4y = 15
make "x" the subject:
x + 7y = 21
x = 21 - 7y .........equation 1
x + 4y = 15
x = 15 - 4y .......equation 2
Solving both the equations simultaneously:
15 - 4y = 21 - 7y
-4y + 7y = 21 - 15
3y = 6
y = 6 ÷ 3
y = 2
If y is 2
Then x = 21 -7y;
x = 21 - 7(2)
x = 21 - 14
x = 7
The mean is 10 because you will add all the numbers and then divide the answer by 4
Answer:
300 seconds
Step-by-step explanation:
First, you have to know how much half a minute is. Half a minute is 30 seconds.
Second, you multiply 30 by 10 because he answered 10 questions.
30 * 10 = 300
So your answer is 300 seconds
Lastly, have a great day! :)
Answer:
.40km or 1/4 a mile
Step-by-step explanation:
