Fractions

Parts of a whole

A fraction shows part of a whole. If a chapati is cut into 4 equal pieces and you eat 1, you ate 1/4. The KICD Grade 6 Mathematics curriculum extends fractions to equivalence, comparison and operations.

Parts of a fraction

In 3/4:

• Numerator (3) = parts taken
• Denominator (4) = total equal parts

Types

• Proper: 3/4 (numerator smaller)
• Improper: 5/4 (numerator larger)
• Mixed number: 1 1/4

Equivalent fractions

Multiply or divide both numerator and denominator by the same number.

• 1/2 = 2/4 = 3/6
• 6/8 = 3/4

Comparing

• Same denominator: the bigger numerator is bigger. 3/5 > 2/5.
• Different denominators: make them the same first. 1/2 and 2/3 become 3/6 and 4/6, so 2/3 is bigger.

Adding and subtracting

Same denominators: work with the numerators only.

• 2/7 + 3/7 = 5/7
• 5/8 - 2/8 = 3/8

Different denominators: find equivalents first.

• 1/2 + 1/4 = 2/4 + 1/4 = 3/4

Real life

A farmer plants maize on 3/5 of the shamba and beans on 1/5. Together that is 4/5, leaving 1/5 empty.

Try it

• Write two fractions equivalent to 2/3.
• Compare 3/4 and 5/8.
• Work out 1/3 + 1/6.