Question

(i) a= 5, d = 3 और a = 50 दिया है।
50 दिया है। n और S ज्ञात​

Answer 1

Question:-

• a = 5, d = 3 and an = 50 are given and find n and Sn.

Answer:-

• We know that,

• an = a + ( n - 1 ) d

• 50 = 5 + ( n - 1 ) 3

• 50 - 5 = 3n - 3

• 45 + 3 = 3n

• 48 = 3n

• n = 16.

• We know that,

• Sn = n/2 [ 2a + ( n - 1 ) d ]

• Sn = 16/2 [ 2 * 5 + ( 16 - 1 ) 3 ]

• Sn = 8 [ 10 + 15 * 3 ]

• Sn = 8 [ 10 + 45 ]

• Sn = 8 * 55

• Sn = 440

Conclusion:-

• Therefore, n ( number of terms ) = 16 and Sn ( Sum of all the terms ) = 440.

Formulas used:-

• an = a + ( n - 1 ) d

• Sn = n / 2 [ 2a + ( n - 1 ) d