3 years ago

Find the sum of the first 20 terms of an arithmetic series if the first term is 10 and the twentieth term is 38.

Mathematics

1 answer:

elena-14-01-66 [18.8K]3 years ago

6 0

Answer:480

Step-by-step explanation:

To find the sum of the first n terms of an arithmetic series use the formula, n terms of an arithmetic sequence use the formula,

Sn=n(a1 + an)2

n=20

a1= 10

a20=38

20(10+38)/2

20(48)/2

960/2

480

So the ans is 480

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What value should go in the empty box to complete the calculation for finding the product of 23.456 × 0.86? 23.456 times 0.86 gi

tester [92]

23,456
x 86

If we calculate the conventional way,
This gives us 23,456 * (6 + 80)
= (23,456 * 6) + (23,456 * 80)

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Next, we multiply 23456 by 80, the figures obtained will be 1,876,480
The third option is the correct answer

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3 years ago

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