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2 years ago

14

8 times of the eight term of an arithmetic progression is equal to 12 times of the twelfth term. find its first term if the comm

on difference is -2 .

1 answer:

denpristay [2]2 years ago

3 0

Answer:

38

Step-by-step explanation:

We can express the 8th term as x and the 12th term as y.

This would mean that 8x=12y

Because the common difference between terms is -2 and term 8 and term 12 are 4 terms apart, this means that the 12th term is 8 less than the 8th term, so x-8=y

Now we can use this to substitute y with x in the first equation. This would give us:

8x=12(x-8)

Which we can expand and solve:

8x=12x-96

-4x=-96

Therefore x=24

This means the 8th term is 24 and the 12th term is 16 (24-8).

To test if this is correct we can do:

8x24=12x16

Which indeed are equal, both sides multiply to 192.

Now that we have our 8th term, we can find the 1st term, which is 7 terms away, therefore we just add 14 to the 8th term 24. (7x2=14)

24+14=38.

The first term is 38.

Hope this helped!

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Answer:

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Step-by-step explanation:

We need the probability of choosing a blue block,

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Answer:

The odds in favor of her character unlocking the treasure chest are 13/7.

Step-by-step explanation:

The probability of Amanda's character unlocking the treasure chest is 13/20.

It means, in 20 total chances, 13 times an event will happen where Amanda's character unlocks the treasure chest while the rest 7 times, her character would not open treasure chest.

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Step-by-step explanation:

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Step-by-step explanation:

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