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Lilit [14]
3 years ago
10

Two grandparents want to pick up the mess that their granddaughter had made in her playroom. One can do it in 15 minutes working

alone. The​ other, working​ alone, can clean it in 12 minutes. How long will it take them if they work​ together?
Mathematics
1 answer:
Crank3 years ago
5 0

Answer:

  6 2/3 minutes

Step-by-step explanation:

Their rates in "jobs per hour" are ...

  (60 min/h)/(15 min/job) = 4 jobs/h

and

  (60 min/h)/(12 min/job) = 5 jobs/h

So, their combined rate is ...

  (4 jobs/h) + (5 jobs/h) = 9 jobs/h

The time required (in minutes) is ...

  (60 min/h)/(9 jobs/h) = (60/9) min = 6 2/3 min

Working together, it will take them 6 2/3 minutes.

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Please help me with this problem! I am so confused: This system of equations shows x by itself on the left side of one equation.
andrew-mc [135]

Answer:

x=-6

y=4

Step-by-step explanation:

x=-y-2        x=-y-2             x=-y-2         x=-y-2         x=-y-2   x=-4-2   x=-6

0.5x+y = 1  0.5(-y-2)+y=1  -0.5y-1+y=1  -y-2+2y=2  y=4       y=4       y=4

7 0
2 years ago
What’s the answer to this equation<br> 4x7=(__x5)+(4x2)
motikmotik

Answer:

4

Step-by-step explanation:

4X7 =28

4X2 =8

28-8 =20/5

=4

5 0
3 years ago
Suppose a computer manufacturer has the total cost function
S_A_V [24]

Answer:

(a)  P(x) = 300 x - 3600

(b)  P(340) = $ 98400

(c)  At least 12 items must be sold to avoid losing money.

Step-by-step explanation:

Part (a):

The Profit function is the difference between the revenue function (R(x)) and the Cost (C(x)) function:

P(x) = R(x) - C(x)

P(x) = 384 x - [84 x + 3600]

P(x) = 384 x - 84 x - 3600

P(x) = 300 x - 3600

Part (b):

The profit on 340 items is:

P(340) = 300 (340) - 3600

P(340) = 102000 - 3600

P(340) = $ 98400

Part (c):

To avoid losing money, the profit P(x) has to be larger or equal than zero. That is:

P(x) \geq 0

300 x -3600  \geq 0

300 x  \geq 3600

x  \geq 3600/300

x  \geq 12

So at least 12 items must be sold to avoid losing money.

7 0
2 years ago
Allyson Greve has calculated her federal taxable income to be $45,300. She pays a state income tax rate of 3% on her federal tax
valentinak56 [21]

Answer:

1,359

Step-by-step explanation:

3% of 45,300 is 1,359

4 0
2 years ago
800+150? please tell me
Sedbober [7]

Answer:

800 + 150 = 950

Step-by-step explanation:

The answer is 950 because if you have $800 and your mom gives you $150 more. You will have a total of $950.

7 0
3 years ago
Read 2 more answers
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