Speed = 308/3 ÷ (1+1+1/3) = 44 km/h.

2. There are X boys.

X-X/ 1 1 = 13 1-X-5

2 1X/ 1 1 = 126

X=66

Boy =66 years old

Girls = 13 1-66=65.

3. Cooperative repair = 4× (110+112) =115.

Also = (1-1115) ÷110 = 8/3 days.

4. The second month = 1-3/7=4/7

A * * * = 200 (4/7-3/7) =1400kg.