28 men are needed to paint the room in 3 hours
<h3><u>Solution:</u></h3>
Given that it takes 12 hours for 7 men to paint a room
We are asked to find number of men required to paint the room in 3 hours
Recognize, "paint the room" is 1 task. One job.
7 men -------- 12 hours ------ 1 job
(7/7) = 1 men ------- 12 x 7 (84) ------- same 1 job
The one men is rate is 84 hours to do the job
We can express this as 1/84 jobs per hour, the one-person rate
Now lets find how many men needed to paint the room in 3 hours
Let the required number of men for 3 hours be "a"
The rates of each person is simply additive.
corresponds to rate x hours = jobs and "a" is a variable for how many men
Thus 28 men are needed to paint the room in 3 hours
Answer:
60 minutes
Step-by-step explanation:
Let the number of minutes be represented as x
For Plan A
Plan A charges $35 plus $0.25 per minute for calls.
$35 + $0.25 × x
35 + 0.25x
For Plan B
Plan B charges $20 plus $0.50 per minute for calls.
$20 + $0.50 × x
20 + 0.50x
For what number of minutes do both plans cost the same amount?
This is calculated by equating Plan A to Plan B
Plan A = Plan B
35 + 0.25x = 20 + 0.50x
Collect like terms
35 - 20 = 0.50x - 0.25x
15 = 0.25x
x = 15/0.25
x = 60 minutes.
Hence, the number of minutes that both plans cost the same amount is 60 minutes
Answer:
(5, - 4 )
Step-by-step explanation:
Given the 2 equations
2x + 3y = - 2 → (1)
3x - y = 19 → (2)
Multiplying (2) by 3 and adding to (1) will eliminate the y- term
9x - 3y = 57 → (3)
Add (1) and (3) term by term to eliminate y
(2x + 9x) + (3y - 3y) = (- 2 + 57), that is
11x = 55 ( divide both sides by 5 )
x = 5
Substitute x = 5 into either of the 2 equations and solve for y
Substituting into (1)
2(5) + 3y = - 2
10 + 3y = - 2 ( subtract 10 from both sides )
3y = - 12 ( divide both sides by 3 )
y = - 4
Solution is (5, - 4 )
<span>2 3/4 = 2.75
so
</span>2 3/4 = 2.75%
