1. Starter Questions Starter Questions 1. Calculate 8796 ÷ 100 2. What is 45 mins expressed as a fraction of an hour? 3. Calculate the area of a circle, with radius 4cm. 4. Find a) -6 – (-3)b) -8 ÷ 4

2. Learning Intention To show how to convert time from hours and minutes to decimals and back again Hrs and Mins in Decimal Time Converting Decimal Time to Hrs Mins

3. Hrs Mins to Decimal Time Converting Hrs Mins to Decimal Time We already know : Example 1 : 48 minutes to decimal is = 0.8 hr Example 2 :2hr 15 minutes to decimal is= 2.25 hr To change minutes to a decimal ‘divide by 60’ 48 ÷ 60 2 + (15 ÷ 60)

4. Hrs Mins to Decimal Time To change minutes to a decimal time ‘divide by 60’ To convert back to hours and minutes we do the opposite : To change decimal time to minutes ‘multiply by 60’ Converting Decimal Time to Hrs Mins

5. Hrs Mins to Decimal Time Example 1 : 0.7 hrs to minutes is = 42 mins Example 2 : 3.4 hrs to hours and minutes is = 3 hrs 24 mins Converting Decimal Time to Hrs Mins To change decimal time to minutes ‘multiply by 60’ 0.7 x 60 3 + (0.4 x 60)

6. Hrs Mins to Decimal Time Converting Decimal Time to Hrs Mins Convert the following hrs and minutes into decimal time: a) 24 minutes b) 40 minutesc) 2 hrs 36 minutes Convert the following decimal time into hrs and minutes: a) 0.35 hrs b) 3.2 hrsc) 0.85 hrs d) 9 minutes e) 21 minutes f) 4 hrs 27 minutes d) 6.9 hrse) 0.8 hrsf) 1.65 hrs

7. Now try Ex 10.5 Pg 99 Q1&2 Time Distance Speed Converting Hrs Mins to Decimal Times