Advertisements
Advertisements
प्रश्न
Write an A.P. whose first term is a and common difference is d in the following.
उत्तर
a = –7, d = `1/2`
t1 = a = –7
t2 = a + d = `-7 + 1/2 = (-14 + 1)/2 = (-13)/2`
t3 = a + 2d = `-7 + 2(1/2)` = –7 + 1 = –6
t4 = a + 3d = `-7 + 3(1/2) = -7 + 3/2 = (-14 + 3)/2 = (-11)/2`
∴ A.P. is `-7, (-13)/2, -6, (-11)/2 .......`
∴ A.P. is –7, –6.5, –6, –5.5 ........
APPEARS IN
संबंधित प्रश्न
How many terms of the A.P. 65, 60, 55, .... be taken so that their sum is zero?
The ratio of the sum use of n terms of two A.P.’s is (7n + 1) : (4n + 27). Find the ratio of their mth terms
If the sum of the first n terms of an AP is 4n − n2, what is the first term (that is, S1)? What is the sum of the first two terms? What is the second term? Similarly, find the 3rd, the 10th, and the nth terms.
200 logs are stacked in the following manner: 20 logs in the bottom row, 19 in the next row, 18 in the row next to it and so on. In how many rows are the 200 logs placed, and how many logs are in the top row?
If the nth term of the A.P. 9, 7, 5, ... is same as the nth term of the A.P. 15, 12, 9, ... find n.
Find the sum of all integers between 100 and 550, which are divisible by 9.
In an A.P., if the 5th and 12th terms are 30 and 65 respectively, what is the sum of first 20 terms?
Find the sum of all 3-digit natural numbers, which are multiples of 11.
Find the sum of the first 15 terms of each of the following sequences having the nth term as
yn = 9 − 5n
Find the sum of all odd natural numbers less than 50.
Find the sum of all natural numbers between 250 and 1000 which are divisible by 9.
Find the sum of all multiples of 7 lying between 300 and 700.
A sum of ₹2800 is to be used to award four prizes. If each prize after the first is ₹200 less than the preceding prize, find the value of each of the prizes
The first term of an A. P. is 5 and the common difference is 4. Complete the following activity and find the sum of the first 12 terms of the A. P.
a = 5, d = 4, s12 = ?
`s_n = n/2 [ square ]`
`s_12 = 12/2 [10 +square]`
`= 6 × square `
` =square`
If the seventh term of an A.P. is \[\frac{1}{9}\] and its ninth term is \[\frac{1}{7}\] , find its (63)rd term.
A piece of equipment cost a certain factory Rs 60,000. If it depreciates in value, 15% the first, 13.5% the next year, 12% the third year, and so on. What will be its value at the end of 10 years, all percentages applying to the original cost?
Mrs. Gupta repays her total loan of Rs. 1,18,000 by paying installments every month. If the installments for the first month is Rs. 1,000 and it increases by Rs. 100 every month, What amount will she pays as the 30th installments of loan? What amount of loan she still has to pay after the 30th installment?
Q.6
Q.5
How many terms of the series 18 + 15 + 12 + ........ when added together will give 45?
