Two quantities are said to be in direct proportion if they increase or decrease in the same ratio. If two amounts are directly proportional we can scale the quantities up by multiplying. 150 ml × 5 = ...

The cost of the pencils (C) is directly proportional to the number of pencils (n). When the proportionality sign (∝) is replaced with an equal sign (=), the equation is \(x = k y\). The constant value ...