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3 years ago

The speed of a boat in still water is 10 km/hr. The boat travels 24 km upstream, turns

Mathematics

1 answer:

Ivan3 years ago

6 0

Answer:

rate of the current = 2 km/hr

Step-by-step explanation:

d = rt

Let c = rate of the current

Rate of boat downstream = 10 + c

Time going downstream = 24/(10 + c)

Rate of boat upstream = 10 - c

Time going upstream = 24/(10 - c)

Since the total time is 5 hr, then

24/(10 + c) + 24/(10 - c) = 5

24(10 - c) + 24(10 + c) = 5(10 + c)(10 - c)

240 - 24c + 240 + 24c = 500 - 5c^2

480 = 500 - 5c^2

5c^2 = 20

c^2 = 4

c = 2 or -2

Since a rate cannot be negative, the rate of the current = 2 km/hr

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Keira , larry and gita picked apples at an orchard. keira picked twice as many pounds as larry and 3 times as many as gita. the

Natalija [7]

Number of apples in pounds picked up by Keira = K
Number of apples in pounds picked up by Larry = L
Number of apples in pounds picked up by Gita = G
Total number of apples they picked all together in pounds = 8360
Now from the given question, we know
Number of apples picked up by Kiera = 2L
So
K = 2L
L = K/2
Again Kiera picked up 3 times as many apples as Gita picked.
So,
K = 3G
G = K/3
Now if we add all the apples in pounds picked up by the three of them.
Then
K + L + G = 8360
K + (K/2) + K/3) = 8360
(6K + 3K + 2K)/6 = 8360
11K/6 = 8360
11K = 8360 * 6
11K = 50160
K = 4560
Then
L = K/2
   = 4560/2
   = 2280
G = K/3
   = 4560/3
   = 1520
Now we can say that
Kiera picked 4560 pounds of apple
Larry picked 2280 pounds of apple
Gita picked 1520 pounds of apple

7 0

3 years ago

Multiply (2.4 ⋅ 1014) ⋅ (4 ⋅ 107). Express the answer in scientific notation

IRINA_888 [86]

9.6*10^21 is your answer

3 0

4 years ago

Read 2 more answers

Mr dambek had $90 to spend at the bulls game he spent 31/45 on his ticket the. He spent 3/7 of his remaining money at the conces

slavikrds [6]

Answer:

He does not have enough money to buy the hat.

Step-by-step explanation:

First find out how much he spent on the ticket:

$90 \times {31 \over 45}=2 \times 31=62$

He spent $62 on the ticket, so he has $90 - $62 = $28 remaining. Now find out how much of that he spent at the concession stand:

$28 \times {3 \over 7}=4 \times 3=12$

He spent $12 at the concession stand, so he has $28 - $12 = $16 remaining. He does not have enough to buy the $18 hat.

6 0

3 years ago

Keisha swims 18 ft from one side of her circular pool to the other, swimming straight through the center. She then swims one tim

elena-s [515]

Answer:

Swimming one time around the pool is 56.5 ft

Step-by-step explanation:

Swimming 18 ft from one side of her circular pool to the other, swimming straight through the center means the circular swimming pool has a diameter of d=18 ft.

The circumference of the circle is calculated using:

$c = \pi \: d$