Answer:
2133 bricks
Step-by-step 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
