Sizu Home › Calculators › Elapsed Time and Making Change
Opens on Chapter 17’s example: soccer from 3:40 to 5:15, and change from $10 for $6.27.
Work back from an end time
The 24-hour clock
Make change by counting up
Count coins
Enter the numbers from the worksheet, then press Show me.
From the book, Chapter 17. 3:40 to 5:15: 20 minutes to 4:00, an hour to 5:00, 15 minutes to 5:15: 1 hour 35 minutes. Taking 4:15 − 2:50 as 415 − 250 = 165 goes wrong because an hour is 60 minutes, not 100. Change from $10 for $6.27: 3 cents to $6.30, 20 cents to $6.50, 50 cents to $7, then $3: $3.73.
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