- #1
martina1075
- 7
- 0
- Homework Statement
- Good morning,
can someone help me solve this please?
Thank you in advance
- Relevant Equations
- As per picture
Cannot conclude the answer
Last edited by a moderator:
It says to evaluate the sum. The answer should be 5. The problem is how he got to 5.PeroK said:That's an interesting one. Does it say what you are supposed to do?
martina1075 said:It says to evaluate the sum. The answer should be 5. The problem is how he got to 5.
That's what I thought at first, hence post #2. But, then, I saw the light!berkeman said:
osilmag said:There should be a table in your textbook for common arithmetic series. There is no way that the answer is 5.
No table is needed.osilmag said:There should be a table in your textbook for common arithmetic series.
See Delta2's hint in post 6.osilmag said:There is no way that the answer is 5.
PeroK said:Read the question carefully!
osilmag said:I did!
Five is if the index stops at one. It doesn't state that in the problem, but it sure tricked me.
PeroK said:Read the question carefully!
Read it even more carefully!osilmag said:I did!
If n = 2, we haveosilmag said:Five is if the index stops at one. It doesn't state that in the problem, but it sure tricked me.
No, the index k counts up from 1 to n. Since the summand doesn't involve k, and so is constant, we're just adding ##5 \cdot \frac 1 n## n times.osilmag said:Ok. I got it! Like I said it tricked me.
I had thought the index counted up from k to n.
Mark44 said:No, the index k counts up from 1 to n. Since the summand doesn't involve k, and so is constant, we're just adding ##5 \cdot \frac 1 n## n times.
But is not the usual definition of "5"!PeroK said:... which is essentially the definition of ##n \times \frac 5 n##.
Evaluating a sum refers to the process of finding the numerical value of an expression that involves addition. This involves following the proper order of operations and performing the addition correctly to arrive at a final answer.
The steps for evaluating a sum are as follows:
To ensure that you have evaluated a sum correctly, you can use a calculator to check your answer. Additionally, you can plug your final answer back into the original expression and see if it simplifies to the same value.
Yes, you can evaluate a sum without using a calculator by following the proper order of operations and using mental math strategies, such as breaking numbers into smaller, more manageable chunks.
Understanding how to evaluate sums is important because it is a fundamental skill in mathematics and is used in various real-life situations, such as calculating expenses or solving equations. It also helps build a strong foundation for more complex mathematical concepts.