Question

2. Evaluate :
(14+3 + 8 + 5 + 12 + 7 + ... to 32 terms.
(17 + 6 9 + + 9 + +
3 Find the sum of all numbers, which are divisible by 7 and lying between 50 and 500.
Find the sum of all integers between 92 and 786, which are multiples of 9.
Find the sum of all natural numbers between 100 and 1000, which are multiples of 5.
Find the sum of all odd integers between 300 and 498.
Find the sum of all integers between 400 and 579, which are divisible by 10.
& Find the sum of all 3-digit numbers, which leave the remainder 1, when divided by 4.
9. How many terms of the sequence – 12, -9,–6, – 3, .... must be taken to make the sum 54?
16. Find the sum of first n natural numbers.
11. Find the sum of first n even natural numbers.
12. Find the sum of all even numbers between 200 to 500.
(13)
13. Show that the sum of first n even natural numbers is equal to 1+ times the sum of firs
n
odd natural numbers.
14. Find the sum of all four digit numbers, which when divided by 25 leaves 5 as a remainder​

Answer 1

Answer:

2. Evaluate :

(14+3 + 8 + 5 + 12 + 7 + ... to 32 terms.

(17 + 6 9 + + 9 + +

3 Find the sum of all numbers, which are divisible by 7 and lying between 50 and 500.

Find the sum of all integers between 92 and 786, which are multiples of 9.

Find the sum of all natural numbers between 100 and 1000, which are multiples of 5.

Find the sum of all odd integers between 300 and 498.

Find the sum of all integers between 400 and 579, which are divisible by 10.

& Find the sum of all 3-digit numbers, which leave the remainder 1, when divided by 4.

9. How many terms of the sequence – 12, -9,–6, – 3, .... must be taken to make the sum 54?

16. Find the sum of first n natural numbers.

11. Find the sum of first n even natural numbers.

12. Find the sum of all even numbers between 200 to 500.

(13)

13. Show that the sum of first n even natural numbers is equal to 1+ times the sum of firs

n

odd natural numbers.

14. Find the sum of all four digit numbers, which when divided by 25 leaves 5 as a remainder

Answer 2

Answer:

Question No 3 :

total number (n)= 50/7 - 500/7 = 64

a = 56

d = 7

$formula \: = \\ n \div 2({2a + < n - 1 > d})$

=64/2 [ 2(56) + (64-1)7 ]

= 32 [ 112+441 ]

= 32 ( 553 )

= 17696

Question No 4 :

total number = 92/9 - 786/9 = 77

a = 99

d = 9

= 77/2 [ 2(99) + (77-1)9 ]

= 77/2 [ 198 + 684 ]

= 77/2 [ 882 ]

= 33957