If factory A turns out x cars an hour and factory B turns out y cars every 2 hours, the number of cars which both factories turn out in 8 hours is?

∵ Factory A turns out x cars in one hour. Factory B turns out y/2 cars in one hour.
⇒ In one hour both the factories A and B can turn out (x + y/2) cars
∴ In 8 hours both factories turn out = 8( x + y/2) cars
= 4(2x + y) cars.