First you need to find the percent equivalent to that of the ratio. The ratio is 3:5. From there you would take the 3, and divide it by 5. 3/5=0.6. Apply that to the information that you are given: 8(0.6)=4.8.
I don't have my calculator handy just now. But just looking at that problem, why don't you try +20 and -45 and see if they do the job.
Answer:

General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Algebra I</u>
<u>Algebra II</u>
- Distance Formula:

Step-by-step explanation:
<u>Step 1: Define</u>
<em>Identify</em>
Point (21, 13)
Point (3, 13)
<u>Step 2: Find distance </u><em><u>d</u></em>
Simply plug in the 2 coordinates into the distance formula to find distance <em>d</em>
- Substitute in points [Distance Formula]:

- [√Radical] (Parenthesis) Subtract:

- [√Radical] Evaluate exponents:

- [√Radical] Add:

- [√Radical] Evaluate:

For 10 gallons of sauce, we need 5 times as required for 2 gallons, therefore we need 4 * 5 = 20 bottles of ketchup.