3 years ago

A series contains 18 numbers and has a sum of 4,185. The last number of the series is 275. What is the first number?

1 answer:

3 0

The sum of arithmetic series is given by:
Sn=n/2(a1+an)
where:
n=number of terms
a1=first term
an=nth term
but
n=18, an=275, Sn=4185
plugging the values in the formula we get:
4185=18/2(a1+275)
simplifying this we get:
4185=9(a1+275)
dividing through by 9 we get:
465=a1+275
thus
a1=465-275
a1=190

Answer: first number is 190

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Answer:

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Step-by-step explanation:

= We solve the above question using the Trigonometric function of Tangent

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3 years ago

(8Q) Tell whether the function exhibits damped oscillation. If it does, identify the damping factor and tell whether the damping

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Answer:

Option c.

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Step-by-step explanation:

We can easily solve this question by using a graphing calculator or any plotting tool.

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Which can be seen in the picture below

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f(x) does not present any dampening