sally can paint a room in 7 hours while it taks steve 9hours to finsh the same room. how ling will it take them to paint if they worked together?
Answers
a ÷ 7 = a/7
And what about Steve ?
a ÷ 9 = a/9
Where, a is the total area of the room.
So, let the time taken by both of them to paint the room together be 't'
So,
t(a/7 + a/9) = a
t(9a/63 + 7a/63) = a
t(16a/63) = a
t = 63/16 ≈ 4 hr
In 7 hours Sally alone does the job.
In 1 hour Sally would do (1/7) of the job.
Steve can paint it alone in 9 hours.
In 9 hours Steve alone does the job.
In 1 hour Steve would do (1/9) of the job.
Both working together in 1 hour would do: (1/7) + (1/9).
(1/7)*(9/9) + (1/9)*(7/7) = 9/63 + 7/63 = (9 + 7) / 63 = 16/63
In 1 hour both will have done (16/63) of the job.
16/63 of the job will be done in 1 hour by both.
Therefore a 1 whole fraction of the job will be done in: 1 hour ÷ 16/63
= 1 hour × 63/16
= 63/16 hours = 3.9375 hours
It would take both 63/16 hours or 3.9375 hours.
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Answers
Answer:
x = 5
Step-by-step explanation:
150+25x= 55x
-25x -25x
150= 30x
150/30 = 30x/30
x = 5
Hope this helps!
Answer: x =5
Steps: 150 + 25x = 55x
Subtract 150 from both sides: 150 + 25x - 150 = 55x - 150
Simplify: 25x = 55x - 150
Subtract 55x from both sides: 25x - 55x = 55x - 150 - 55x
Simplify: -30x = -150
Divide both sides by -30: -30x ÷ -30 = -150 ÷ -30
Simplify: x = 5
Plz mark brainliest:)
/12
2
-0.1/144
√43
57
10
Answers
Answer:
the answer is 01
Step-by-step explanation:
Answer:
01
Step-by-step explanation:
Answers
How much does a bottle of water cost?
How much does a gallon of milk cost?
Answers
Answer:
Cost of a snack size bag of chips = $0.8
Cost of a water bottle = $1.6
Cost of a gallon of milk = $3.4
Step-by-step explanation:
Let the cost of water bottle = $a
Cost of 1 gallon milk = $b
and cost of 1 bag of chips = $c
So, cost of 4 gallons of milk, 6 bottles of water and 5 bags of chips = $(4b + 6a + 5c)
4b + 6a + 5c = 27.2 -----(1)
Cost of one water bottle = 2 × cost of one bag of chips
a = 2c -----(2)
A gallon of milk = cost of water bottle + $1.80
b = a + 1.8
From equation (2)
b = 2c + 1.8 -----(3)
Now we substitute these values from equations (2) and (3) in equation (1)
4(2c + 1.8) + 6(2c) + 5c = 27.2
8c + 7.2 + 12c + 5c = 27.2
25c = 27.2 - 7.2
c =
c = $0.8
From equation (2)
a = 2×0.8
a = $1.6
From equation (3)
b = 2(0.8) + 1.8
b = 1.6 + 1.8
b = $3.4
Therefore, cost of a snack size bag of chips = $0.8
Cost of a water bottle = $1.6
Cost of a gallon of milk = $3.4
A.) 1
B.) 6
C.) x
Answers
b. 9.1 cm
c. 14.2 cm
d. 11.2 cm
Answers
The lateral area (LA) of the cone can be expressed as:
LA = π * r * l
r - the radius of the cone
l - slant height of the cone
It is given:
l = ?
r = 50 cm
LA = 500π cm²
Let's replace these in the equation for the lateral area of the cone:
500π = π * 50 * l
500π = 50π * l
⇒ l = 500π/50π
l = 10 cm