Advertisements
Advertisements
Question
The first three terms of an AP are respectively (3y – 1), (3y + 5) and (5y + 1), find the value of y .
Advertisements
Solution
The terms (3y -1), (3y +5) and (5y +1) are in AP.
∴ (3 y + 5) - (3y-1) = (5y+1) - (3y+5)
⇒ 3y + 5-3y +1 = 5y + 1-3y-5
⇒6 = 2y-4
⇒ 2y = 10
⇒ y = 5
Hence, the value of y is 5.
APPEARS IN
RELATED QUESTIONS
Find the sum of all natural numbers between 250 and 1000 which are exactly divisible by 3
The ratio of the sums of m and n terms of an A.P. is m2 : n2. Show that the ratio of the mth and nth terms is (2m – 1) : (2n – 1)
Find the sum of the following arithmetic progressions:
−26, −24, −22, …. to 36 terms
Find the sum of first n odd natural numbers
Find the sum 25 + 28 + 31 + ….. + 100
The 8th term of an AP is zero. Prove that its 38th term is triple its 18th term.
Find the three numbers in AP whose sum is 15 and product is 80.
Find the sum of first n terms of an AP whose nth term is (5 - 6n). Hence, find the sum of its first 20 terms.
The sum of the first n terms of an AP in `((5n^2)/2 + (3n)/2)`.Find its nth term and the 20th term of this AP.
If the common differences of an A.P. is 3, then a20 − a15 is
Write the common difference of an A.P. whose nth term is an = 3n + 7.
Write the value of x for which 2x, x + 10 and 3x + 2 are in A.P.
The first and last terms of an A.P. are 1 and 11. If the sum of its terms is 36, then the number of terms will be
If four numbers in A.P. are such that their sum is 50 and the greatest number is 4 times, the least, then the numbers are
Two A.P.'s have the same common difference. The first term of one of these is 8 and that of the other is 3. The difference between their 30th term is
The common difference of the A.P.
Q.3
If the sum of the first four terms of an AP is 40 and that of the first 14 terms is 280. Find the sum of its first n terms.
The sum of all two digit numbers is ______.
The sum of A.P. 4, 7, 10, 13, ........ upto 20 terms is ______.
