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Why?. Think of multiplying fractions 2 x = = 1 . 1 2. 2 2. Find the reciprocal of :. 1 2. 1 2. x = 1. Reciprocals. A reciprocal is the value used to multiply a number by to make the product 1. Find the reciprocal of 2:. What do we multiply 2 by to get
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Why? Think of multiplying fractions 2 x = = 1 1 2 2 2 Find the reciprocal of : 1 2 1 2 x = 1 Reciprocals A reciprocal is the value used to multiply a number by to make the product 1 Find the reciprocal of 2: What do we multiply 2 by to get a product of 1? 1 2 2 x = 1 Multiplication is commutable 2 Find the reciprocal of 3: What do we multiply 3 by to get a product of 1? 1 3 3 x = 1 Find the reciprocal of 10: What do we multiply 10 by to get a product of 1? 1 10 10 x = 1
3 4 Find the reciprocal of : What do we multiply by to get a product of 1? 3 4 3x = 12 = 1 4 12 4 3 7 10 0.7 = 10 7 3 7 3 7 Now change into a mixed number 1 1 Reciprocals 3x = 1 4 4 3 Remember how to multiply fractions: Find the reciprocal of 0.7 : 7 x = 1 10 10 7 So the reciprocal of 0.7 is
2 3 Find the reciprocal of 2 Reciprocals First write the mixed number as a top heavy fraction 3 8 8 3 then follow the same process Now you know the principles the shortcut to finding a reciprocal is to swap the numerator and denominator over 8 8 x = 1 3 3
Now do these Find the reciprocals of: 1. 6 7. 2. 7 8. 0.3 3. 0.25 9. 0.125 4. 10. 1 5. 11. 1.25 6. 12. 1.6 2 3 1 3 3 11 3 3 3 4 1 8 1 12 . 2 7 1 2 3 Reciprocals 1 6 1 7 4 8 4 7 8 4 5 12 3 5