Answer:
17.5hrs
Step-by-step explanation:
Set they worked for x hours,
10x+35=210
10x=175
x=17.5
p(p+q-qr)
p^2+pq-pqr
Factor out a p
12 minutes
4 minutes= 7 kilometers
=> 4*3 minutes= 7*3 kilometers
=12minutes=21km
Answer: 10
Just divide 40 by 4 and you get 10