Answer:
-45
Step-by-step explanation: no explanation
This is an arithmetic sequence with the common difference being 1
and if u have 1 cent on day 1 and 2 cents on day 2....then on day 40, u would have 40 cents....but we need the sum of all the days..
the sum of an arithmetic sequence can be found using the formula :
sn = n(a1 + an) / 2
n = number of terms = 40
a1 = first term = 1
an = last term = 40
now we sub
s(40) = 40(1 + 40) / 2
s(40) = 40(41)/2
s(40) = 1640/2
s(40) = 820.....820 cents = $ 8.20 <== the sum
Using proportions, it is found that the federal tax rate is of 10%.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
The tax rate is the <u>proportion that $17.50 is of $175</u>, hence:
r = 17.50/175 = 0.1 = 10%.
The federal tax rate is of 10%.
More can be learned about proportions at brainly.com/question/24372153
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