Question

Please answer these maths questions. Those who really answer every questions perfectly I'll make their answers a brainliest answer.

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Answer 1

Answer:

For (i) a = 2 d = 5

Ans:- 245

For (iii) a = 0.6 d = 1.1

Ans:- 1101

Answer 2

CONCEPT :

solving these types of questions, you should be familiar with the formula of sum of the arithmetic progression and factorization of quadratic equation. Some students use the formula to find the sum = S = n/2 (a + l ) where l is Last terms but we do not have the value of l

. So, we will here use = S = n/ 2 ( 2a + (n-1 ) where a is the first term and d is common differ

SOLUTION :

i ) a = 2 , d = 7 - 2 = 5 , n = 10

→ s^n = n/2 [ 2 a + (n - 1 ) d]

→ s^10 = 10/2 [ 2× 2+ ( 10- 1 ) 5]

→ 5[4 + 9 × 5] = 5[4 + 45] = 5 × 49

→ S1^0 = 245

ii ) a = 0.6 , d = 1.7 - 1.6 = 1.1 , n = 100

formula = sum = n/2 ( 2a + (n- 1) d)

→ 100/2 ( 2x 0.6 + (100 -1 ) x ( 1.1 )

→ 50 (1.2 + 99 x 1.1 )

→ 50 ( 1.2 + 108.9 )

→ 50 ( 110.1. )

→ 50× 110 .1

→ 5505

thanks !