Step-by-step explanation:
You can just divide 10 by 2/5 and you get 25 or try this
Set up proportions and cross multiply 2/5 / 1 = 10/x which you can read as : if 2/5 can be done in 1 hour then 10 tons can be done in x hours cross multiplying, you get 2x/5 = 10 and x = 25