To answer this, you can use a proportion.
We're trying to figure out what a portion of the 120g tube of ointment so that is our first side of the proportion: ?/120
We know that we can represent percentages as fractions by placing the percent over 100. So this is our second side of the proportion: 4/100
Our partially completed proportion is this: ?/120=4/100
Cross multiply 120 and 4: 120*4=480
Divide the product by 100: 480/100=4.8
So, there is 4.8g of hydrocortisone in the ointment.
