If the 11th and the 8th terms of an arithmetic progression are in the ratio 2 : 5, which of the following statements is definitely false?The sum of no two consecutive terms is zero.The sum of no three consecutive terms is zero.At least one of the terms is zero.None of the above
Question
If the 11th and the 8th terms of an arithmetic progression are in the ratio 2 : 5, which of the following statements is definitely false?The sum of no two consecutive terms is zero.The sum of no three consecutive terms is zero.At least one of the terms is zero.None of the above
Solution
In an arithmetic progression (AP), the difference between any two successive terms is constant. This constant difference is called the common difference.
Given that the 11th and 8th terms of an AP are in the ratio 2:5, we can write this as:
2/5 = (a + 10d) / (a + 7d)
where a is the first term and d is the common difference.
Solving this equation, we get:
2a + 20d = 5a + 35d
Simplifying, we get:
3a = 15d
So, a = 5d
Now, let's examine the statements:
- The sum of no two consecutive terms is zero.
This statement can be false. If the common difference is not zero, there can be two consecutive terms whose sum is zero. For example, if a = 5 and d = -5, then the first term is 5 and the second term is 0, so their sum is zero.
- The sum of no three consecutive terms is zero.
This statement can also be false. If the common difference is not zero, there can be three consecutive terms whose sum is zero. For example, if a = 5, d = -5, then the first three terms are 5, 0, and -5, so their sum is zero.
- At least one of the terms is zero.
This statement can be true or false, depending on the values of a and d. If a = 5 and d = -5, then one of the terms is zero. But if a = 5 and d = 1, then none of the terms is zero.
- None of the above
This statement is definitely false, because we have shown that the first two statements can be false and the third statement can be either true or false. Therefore, it is not true that none of the above statements is definitely false.
Similar Questions
Which of the following statements are true for an arithmetic pattern? The pattern has a constant second level difference between consecutive terms.The pattern has a constant ratio between consecutive terms.The pattern has a constant difference between consecutive terms.None of the options given are true.
Arithmetic Progressions
In an arithmetic sequence, the first term is 2 and the second term is 5.(a) Find the common difference. [2](b) Find the eighth term. [2](c) Find the sum of the first eight terms of the sequence.
n a certain arithmetic progression, the sum of the first and fifth terms is 18 and the fifth term is 6 more than thethird term. Find the sum of the first ten terms of the progression
The sum of two consecutive terms of a progression is 237 while the difference between those terms is 5. If the first term of the progression is 11 and the difference between two consecutive terms of the progression is the same, then what are the respective positions of those two consecutive terms?
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.