December 6, 2011
We have been learning how to develop our skills, in speaking, reading, and writing the English language. Did you know that when we were in math class, we were also learning how to speak, read, and write the language of mathematics? Mathematics uses numbers and number systems instead of the alphabet, but it's also a language: a language of patterns and symbols. Mathematics can help you recognize, understand, describe and identify changes in patterns. Problem35.
A person hired a firm to build a CB radio tower. The firm charges $100 for labor for the first 10 feet. After that, the cost of the labor for each succeeding 10 feet is $25 more than the preceding 10 feet. That is, the next 10 feet will cost $125, the next 10 feet will cost $150, etc. How much will it cost to build a 90-foot tower? Here is how we think about it:
We see that there is a new price every ten feet as they build the tower. After that the cost of the labor for each succeeding 10 feet is $25 more than the preceding 10 feet. That is, the next 10 feet will cost $125, the next 10 feet will cost $150, etc. How much will it cost to build a 90-foot tower? n= the number of terms altogether n=9
d= the common difference d=25
a1= the first term a1=100
aN= the last term aN=a9 (yet to be computed) Next, we need to compute what a9 is. The next step is to find the nth term of the sequence, or the 9th term in this case. aN=a1+(n-1)d
Now that we know what a9 is, we need to know what the sum of the sequence is from a1 to a9. The next step is to find the answer to this question. Sn= n(a1+a9)/2
A person deposited $500 in a savings account that pays 5% annual interest that is compounded yearly. At...