Answer: The answer is 400 blue marbles.
Step-by-step explanation: Given that there are 560 marbles in a bag, out of which 65% are red and rest are blue.
So, number of red marbles is

and number of blue marbles is

Now, if 28 red marbles are replaced by blue marbles, the the new number of red and blue marbles will be

Now, to get 65% of the marbles blue, we need to add some more blue marbles to the bag. Let 'x' number of blue marbles are added to the bag, then

Thus, 400 blue marbles need to be added to the bag.
Answer:
5
Step-by-step explanation:
The constant of proportionality based on the situation is 0.4
Step-by-step explanation:
Tanner cycled 8 miles in 20 minutes
We need to find the constant of proportionality based on the situation
1. The distance is proportion to the time, because the distance and
the time increased together
2. If the distance d and the time is t, then d ∝ t
3. The equation of the direct proportion is d = k t, where k is the
constant of proportionality
∵ d = k t
∵ d = 8 miles
∵ t = 20 minutes
- Substitute these values in the equation above
∴ 8 = k (20)
- Divide both sides by 20
∴ k = 0.4
The constant of proportionality based on the situation is 0.4
Learn more:
You can learn more about proportionality in brainly.com/question/10708697
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It’s equal to 1/2 in simplest form