Question

If 5" +55 +5”+5" +$" = (15)"
then n =​

Answer 1

HEYA DUDE

HERE IS YOUR ANSWER MATE ❤️

First of all take 5 common like this

5(1+11+111+....n)

then multiply and divide by 9

5/9*9(1+11+111+....n)

5/9(9+99+999.....n)

now we can write 9 like this

5/9[(10-1)+(10*10-1)+(10*10*10-1).....n)

now

5/9(10+10*10+10*10*10....n)-[1+1+1+1....n)

so here a=10, r=10, r>1

so use this formulae

S=a(r to the power n -1 )/r-1

=5/9 ( 10( 10 to the power n - 1) /10-1)-n

=5/9 (10/9( 10 to the power n -1)-n

= 50/81 ( 10 to the power n -1) -5/9n this is the answer have fun.

THANK YOU ❤️

MAY THIS HELPS YOU

HAVE A GREAT DAY ✌️