Answer: 8100 seconds
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Work Shown:
1 hour = 60 minutes
2 hours = 120 minutes (multiply both sides by 2)
1/4 hour = 15 minutes (divide both sides of the first equation by 4)
2 & 1/4 hours = 2 hours + 1/4 hour
2 & 1/4 hours = 120 minutes + 15 minutes
2 & 1/4 hours = 135 minutes
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1 minute = 60 seconds
135 minutes = 8100 seconds (multiply both sides by 135)
2 & 1/4 hours = 8100 seconds