Capacity in Maths – Definition, Types, Examples

Key Concepts

• Identify customary units of measurement for capacity.
• Use multiplication and division to determine the customary measurement equivalences.
• Use measuring tools and purpose of meaning.

Introduction: 

Capacity in Maths:

Capacity is the total amount of fluid that can be contained in a container, It is the word we use when we measure liquid. 

We use multiplication and division to determine customary measurement equivalencies. 

Vocabulary 

Gallon 

Quart 

Pint 

Cup 

Fluid Ounce 

Notes- Capacity term is use to measure the amount of liquid in the container. 

Some basic Customary Unit of capacity and relation between. 

Quantity of Customary units of Capacity (Approximate) 

1. 1 Fluid ounce: – Is equal to the volume of a small medicine cap. 

2. 1 Cup: – A small glass holds about 8 fluid ounces. 

3. 1 Pint: – A large glass of milk. 

4. 1 Quart: – When we want to use many cups of liquid and put them together, we might want to use a quart. 

5. Gallon: – If we still need more liquid, we can switch to gallon. 

Conversion between the units of Capacity 

To convert larger unit to a smaller unit, we multiply. 

Example1:  

Example2:  

To convert smaller unit to a larger unit, we divide. 

Example 1:  

Example 2:  

Observe the image carefully and try to solve the questions based on conversion between the units of capacity. 

1. 14 pints to quart 

Solution: –  

Since, 1 quart = 2 pints 

Therefore, 1 pint = ½ quart 

Now, for 14 pints = ½ ×14  

       = 7 quarts(qt) 

2. 8 gallons to pint 

Solution: –  

Since, 1 gal = 8 pints 

Therefore, 8 pints = 8 × 8  

       = 64 pints(pt) 

3. 18 ½ quart to cups 

Since, 1 quart = 4 cups 

Therefore, 18 ½ qt = 18 × 4 + ½ × 4 

          = 72 + 2   

          = 74 cups 

4.    64 quarts to gallons 

  Solution: –  

Since, 1 gallon = 4 quarts 

Therefore, 1 quart = ¼ gallon 

Now, for 64 quarts = 64 × ¼   

       = 16 gallons (gal) 

5.   13 cups to quarts 

Solution: –  

Since, 1 quart = 4 cups 

Therefore, 1 cup = ¼ quart 

Now, for 13 cups = 13 × ¼   

       = 12-quart 1cup (12qt 1c) 

Real life applications based on units on Capacity (Word Problems) 

1. A tall glass can hold 2 pints and a big mug can holds 34 oz. Which one holds more? 

Solution: – Since 1 pt = 16 oz 

So, 2 pints = 16 × 2 = 32 oz(ounces)  

Therefore, A big mug can hold more.  

2. How many ounces are there in 4 quarts? 

Solution: Since 32 fl. Oz (fluid ounces) = 1 quart (qt) 

So, 4 qt = 32 × 4 = 128 fl. oz 

3.  John made some mashed onion. For every two onions he boiled, he added 2 ounces of milk. If he boiled 16 onions, how much milk did he add to the mashed onion?  

Solution: 16 ÷ 2  

     = 8 fl oz  

Concept Map: 

What have we learned:

• Students have learned about the identification of units of capcity
• Covert smaller units to large unit
• Convert larger unit to smaller unit.
• With different model of images student have learnt the real-life applications of capacity