Answer: 18
Step-by-step explanation:
80 - 44 = 36
36 / 2 = 18
Answer:
x+7y
Step-by-step explanation:
First off, lets split the question into both x and y.
3x - 2x for the x
11y - 4y for the y
You can solve both of them to get x + 7y
3x - 2x = x
11y - 4y = 7y
Then, add them back up and get x + 7y
Short Answer: 18 minutes
Remark
The answer to this problem is less than the smallest time of the two people working together. that fact lets out C and D (38 minutes and 75 minutes). Now you have to choose 15 minutes and 18 minutes. There's a method. No guessing needed.
Givens
Let the time for Sophie = S
Let the time for Simon = M
Let the job to completion = 1
S = 45 minutes
M = 30 minutes
Step One
Convert minutes to hours.
45 minutes = 45 / 60 = 3/4 hour = 0.75 hour
30 minutes = 30 / 60 = 1/2 hour = 0.50 hour
Step Two
Set up the Equation
The formula is a form of job / hour.
Let the time = t that they both have to work
job = 1 in these problems.
1/S + 1/M = 1/t
1/0.75 + 1/0.5 = 1/t
Solve
1 ÷ 0.75 = 1.33333
1 ÷ 0.5 = 2
1.3333 + 2 = 3.33333
3.3333 = 1 / t Multlply both sides by t
3.3333*t = 1
t = 1 / 3.333333333
t = 0.3 of an hour
1 hour = 60 minutes
0.3 hours = x Cross Multiply
x = 60 * 0.3
x = 18 minutes
Answer working together it took them 18 minutes <<<<<
Answer:
1
Step-by-step explanation:
-2(x-4)+1=7
First Distribute the -2.
-2x+8+1=7
Subtract the 8 and 1 from the whole equation.
-2x=-2
Divide both sides of the equation by -2.
x=1
I hope this helps!
