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3 years ago

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There is a mountain with 30 bat caves in a row that contain 340 bats in all. Any 7 caves in a row contain exactly 77 bats. Suppo

se the first cave has 7 times more bats than the last caves. How many bats in the 29th cave?

1 answer:

Anna007 [38]3 years ago

7 0

Answer:

The 29th cave has 28 bats.

Step-by-step explanation:

It is given that any 7 caves in a row contain 77 bats.

So, out of the 30 caves, let us start counting from the second cave till the 29th cave(counting 28 caves).

7 times 4 gives us 28, which has $77\times4=308$ bats. We have not counted the first and last cave.

Let the number of bats in the last cave be $x$ , then according to the question:

$7x+x=340-308=32$ (First cave has 7 times more bats than the last cave)

Hence, $x=4$ (number of bats in the 30th cave)

Now we shall again count, but this time from the first cave, leaving out the last 2 caves. So the total number of bats in the first 28 caves is 308 and 32 in the last 2 caves.

So, the number of bats in the 29th cave = 32 - 4 = 28

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