You can use it by just multiplying and moving the decimal.
I need $100 for my game console I want. I already have $40 and I get $10 every week for doing chores.
Answer:

Step-by-step explanation:
let distance between farmhouse and road is 2 km
From diagram given
p is the distance between road and past the intersection of highway
By using Pythagoras theorem

differentiate wrt t
we get




putting p = 3.7 km


Find 10% then times it by four then find 4% and add it on to get 320.21