Question

5 indistinguishable balls are placed in 6 cells find probability of 1st and 3rd cells are empty​

Answer 1

Answer:

Let a and d be the first term and common difference for an AP.

number of terms of AP = n

last term = nth term = l

Given:

a = 17

d = 9 ,

l = 350

a + ( n - 1 ) d=nth term

=> 35017 + ( n - 1 ) 9 = 350

=>( n - 1 ) 9 = 350 - 17

=>( n - 1 ) 9 = 333

=>n - 1 = 333 /9

=>n - 1 = 37

=>n = 37 + 1

=>n = 38

Therefore ,

Number of terms in given AP =

\pink{\bold{n=38}}n=38

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The terms are:-

\red{17, 26, 35....350}17,26,35....350

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Additional:

How to find the sum of the terms of AP?

let Sum of n terms of AP = Sn

We know,

Sn = n /2 ( a + l )

Here n= 38 (as we calculated)

putting values we get:

Sum = 38 / 2 [ 17 + 350 ]

= 19 × 367

= 6973