# How do you estimate using compatible numbers?

**Compatible numbers**are pairs of**numbers**that are easy to add, subtract, multiply, or divide mentally. When**using estimation**to approximate a calculation, replace actual**numbers**with**compatible numbers**.- Example 1 (Addition) 500 + 300 = 800.
- Example 2 (Subtraction) 19.4 − 3.8 = 15.6.
- Example 3 (Multiplication)

Similarly one may ask, what is the difference between rounding and compatible numbers?

We use **compatible numbers** to make the problem easier to solve in our head by **rounding** each **number** to the nearest ten, twenty, fifty or hundred. But if we make the **numbers compatible** and **round** up to the nearest hundred or ten spot, 300 and 350 are much easier to compute in our heads.

Secondly, what are some examples of compatible numbers? **Some examples of compatible numbers** when doing addition are 225 **and** 75, 298 **and** 2, **and** 540 **and** 60. **Some examples of compatible numbers** when doing subtraction are 435 **and** 25, 800 **and** 600, **and** 5986 **and** 2986.

Similarly, you may ask, what does it mean to estimate the quotient?

**Estimating quotients** isn't that hard so long as you use compatible numbers! A **quotient is** the answer you get after dividing one number by another, and compatible numbers are numbers that are close to the numbers in question yet can divide one another easily.

Which number is compatible with 240?

a highly composite **number** since it has 20 divisors total (1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 40, 48, 60, 80, 120, and **240**), more than any previous **number**. a refactorable **number** or tau **number**, since it has 20 divisors and 20 divides **240**.