Everyday Mathematics

Everyday, whether we realize it or not, we use some form of mathematics. For the purposes of this blog entry, I would like you to make a log. Choose one day to begin logging every instance in which you use mathematics. You might be surprised, if you really pay attention, to how much math you use without even knowing it. Here is an example of my log:

7:45 Am - Wishing to spend less than $10 on breakfast, I add the prices of my items before I purchased them this morning. 5 hour energy - 2.99, Soft Pretzel - .65, Breakfast sandwich - 1.99, Large Bottled Water - 1.35. Without actually adding the numbers, I rounded, and found I'd be spending about $7.

8:05 Am - Will I be late? I need to get to class by 8:30. On the parkway this morning I wondered if I would have enough time to get to class on time. I started at mile marker 25 and needed to get to mile marker 45 in 25 minutes. If I obeyed the speed limit at 65 mph, could I make it on time? 60 mph is the same as saying 1 mile for every minute. So assuming I go 60 mph the whole way, I would be there in 20 minutes. Considering I go about 75 on the parkway, I have plenty of time.

9:45 Am - I have 4 hours between classes with 3 assignments to do. Subtract an hour for food breaks and bathroom breaks and I should spend no more than 60 minutes on each assignment.

2:10 Pm - Calculus class. =D

6:00 Pm - Stop for gas on the way home. I drove 405 miles from my last fill up and (according to my receipt) burned 17.2 gallons of gasoline. My tank holds 18 gallons so I was .8 gallons away from running out of gas.
Also, I wanted to see if my car was running as efficiently as it should. I should be getting about 25 miles per gallon if everything is running correctly. So I checked. If 17.2 gallons gets me 405 miles then 405/17.2 = 23.25 mpg. Hmm... maybe I should check my tires.
I also added my mileage for the week. I wanted to see how much money I should fit into my budget for gas. I drive about 325 miles per week. At 23.25 mpg, I'd be looking at buying about 14 gallons of gas per week. At $2.50 per gallon, I should figure on spending $35 a week on gas.

11:00 Pm - For what time should I set my alarm? I have to be at class at 10:30 Am. Subtract 30 minutes for commute. Subtract 20 minutes for getting ready (getting dressed, brushing teeth, etc.) and 10 minutes for a shower. For a total of 1 hour. I should set my alarm for 9:30 Am.