Question

Pls help asap it math

Answer 1

2133 bricks

Explanation:

a27=1

a4=139

a27=a4+23r

1=139+23r

23r=1-139

23r=-138

r=-138/23=-6

a4=a1+3r

139=a1-18

a1=139+18

a1=157

n=a1+......+a1+26*r=a1+a1+r+......+a1+26r=27*a1+r(1+2+...+26)

=27*157-6*26*27/2=4239-3*26*27=4239-2106=2133