Answer
105 feet
Work Step by Step
f= fire truck, m = ambulance
$3f+4m +6=152$
$2f+5m+6 = 136$
$3f+4m +6-6=152-6$
$2f+5m+6 -6= 136-6$
$3f+4m = 146$
$2f+5m = 130$
$-2*(3f+4m = 146)$
$3*(2f+5m = 130)$
$-6f-8m =-292$
$6f+15m=390$
$-6f-8m+6f+15m =-292 + 390$
$7m = 98$
$7m/7=98/7$
$m=14$
$3f+4m=146$
$3f+4*14 = 146$
$3f+56 = 146$
$3f+56-56 = 146-56$
$3f=90$
$3f/3=90/3$
$f=30$
$30*1+5+14*5 = 30+5+70$
$30+5+70 = 105$
