**Elementary School Number Sense Lesson 12: Ratios**

This lesson is similar to

**MoneyRatio**, but without the money (of course). It has appeared

**5 times**so far this year, with a median placement at

**question # 35**.

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**Number Dojo Level: 107**

These problems are usually worded like this:

**a is to b as c is to d,**

**a c**

---- = ----

b d

---- = ----

b d

**Example 1: 7 is to 5 as ___ is to 30**

- 7/5 = x/30
- 7(30) = 5x --> 210 = 5x
- x = 210/5 =
**42**

**Example 2: 18 is to ___ as 6 is to 11**

- 18/x = 6/11
- 18(11) = 6x --> 3(11) = x
- x =
**33**

**Example 3: n is to 24 as 3 is to 4. What is n? ___**

- n/24 = 3/4
- n = 3/4 (24) = 72/4
- n =
**18**

**Example 4: Seven is to six as fourteen is to n. What is n? ___**

- 7/6 = 14/n
- Cross-multiply. 7n = 6(14)
- n = 6(2) =
**12**

**Example 5: Six is to twenty-five as twelve is to n. What is n? ___**

- 6/25 = 12/n
- Cross-multiply. 6n = 25(12) = 300
- n = 300/6 =
**50**

**Up Next for Elementary School: SubFracSame**