Question

( ͡° ͜ʖ ͡°)︻̷┻̿═━一- hey guys....gud morning⚽
question for maths expert....

Answer 1

As no of terms is even

So no of terms at odd places and even places would be same

let it be n

So total no of terms = 2n

Sum of n terms = 24

n/2 ( 2a + ( n-1)2d) = 24
n( a + ( n-1)d) = 24

As odd places difference would be double

Also n/2( 2( a+d) +( n-1) 2d) = 30
as first even term is a+d

n( a + d + (n-1)d)= 30

n( a + (n-1)d) + nd = 30

24 + nd = 30

nd = 6



As last term = first term +10.5

a + ( 2n-1)d = a + 10.5


2nd - d = 10.5

12 - d = 10.5

d = 1.5

n = 6/1.5 = 4

So no of terms = 2n = 8