50 , 75 , 100
What is the term-to-term rule for the sequence above?
We have hundreds of course questions with personalized recommendations + Account 100% premium
50 , 75 , 100
What is the term-to-term rule for the sequence above?
To find the term-to-term rule for the sequence 50, 75, 100, let's follow these steps:
Now, let's proceed with the solution:
Step 1: Calculate the difference between successive terms:
75 - 50 = 25 and 100 - 75 = 25.
The common difference is 25.
Step 2: Use the arithmetic sequence formula , where here and .
We substitute these values into the formula:
Expand and simplify the formula:
Combine like terms:
Step 3: To match it with the provided choices, manipulate the equation to solve for the sequence terms in reverse. Let's see the alternative derivation:
Reworking in negative order as per choice hint:
Verify by substituting values :
The sequence 100, 75, 50 matches our structured reverse order. Therefore, the matching formula is re-arranged, providing choice calculation:
The term-to-term formula for the sequence is . This matches correct option 1.
12 ☐ 10 ☐ 8 7 6 5 4 3 2 1
Which numbers are missing from the sequence so that the sequence has a term-to-term rule?
The correct formula actually represents the sequence in reverse order! When n = 1, you get 100 (the 3rd term), when n = 2, you get 75 (the 2nd term), and when n = 3, you get 50 (the 1st term).
Calculate the difference between consecutive terms: 75 - 50 = 25 and 100 - 75 = 25. Since both differences equal 25, this is your common difference!
You can write it as , but this doesn't match the given answer choices. Always check what form the question expects!
Substitute values! For : when n = 3, you get . Check that this matches the sequence position you expect.
Absolutely! When the common difference is negative, the sequence decreases. In this case, we're looking at the sequence from a different perspective where the formula counts backwards through the terms.
Get unlimited access to all 18 Series questions, detailed video solutions, and personalized progress tracking.
Unlimited Video Solutions
Step-by-step explanations for every problem
Progress Analytics
Track your mastery across all topics
Ad-Free Learning
Focus on math without distractions
No credit card required • Cancel anytime