# Clock problem algebra

Zermelo—Fraenkel set theory provided a series of principles that allowed for the construction of the sets used in the everyday practice of mathematics, but they did not explicitly exclude the possibility of the existence of a set that belongs to itself. GO Telling Time Being able to tell and work with time is a very valuable skill. In order to tell time, there are several key points to remember.

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We measure time in seconds, minutes, hours, days, weeks, months, and years. On a clock, we measure time in hours and minutes and sometimes seconds.

On a calendar, we measure time in days, weeks, months, and years. This section will go through telling time on a clock—using minutes and hours. In order to work with minutes and hours, you must remember that there are 60 seconds in a minute, and 60 minutes in an hour. There are 24 hours in one day.

Parts of a Clock A clock is a device used to tell time. Clocks measure time in hours and minutes, and have an hour hand that moves forward one clock number every hour and a minute hand that moves forward one tick every minute—it moves forward one clock number every 5 minutes.

One complete trip around the clock by the minute hand means that one hour has passed. When you read a clock, you look at the hour hand first, and then you look at the minute hand.

The hour hand is shorter, and the minute hand is longer—this is how you tell them apart. A normal clock looks like this: The blue numbers are standard on all clocks—these are clock numbers. You will not see the orange numbers on normal clocks the way they are on the outside of this clock, but these are the minute marks—thus, every 1 clock number is equal to 5 minutes. It can be even further broken down like this: Now, you can see that the orange numbers on the outside count from 1 to These numbers represent each minute of an hour.

Remember, the hour hand is shorter, and the minute hand is longer. Notice that our clock hands have arrows—some clocks have hands with arrows, and others do not. We will show ours with arrows. The hour hand is the shorter of the two clock hands.

It moves from one clock number to the next every hour, and it makes one complete rotation around the clock every 12 hours since there are 12 clock numbers on each clock.

Look at which clock number the hour hand is pointing to. That is the number you will use for the hour. Many times, the arrow will not be pointing exactly at the number; in that case, you would look at which number it was at most recently. For example, if the hour hand is half way between the 2 and the 3, you would use 2 as the hour number. The only way you can use a specific number for the hour number is if it has already passed the number in its rotation around the clock.

So, even if the hour hand is very close to the 3, you would still say 2 unless the hand has reached, or passed, the 3. Here, you can see that the hour hand is a little more than half way between the 1 and the 2. Even though it is closer to the 2, we would still say that 1 is our hour number because the hour hand has not passed 2 yet.

The minute hand is the longer of the two hands. It points to the minutes that have passed since a new hour began. It makes one rotation around the clock every hour. If the minute hand is pointing to a clock number, that means the number of minutes is a multiple of 5 5, 10, 15, 20 etc and you would give that number as the number of minutes.

For example, if the minute hand is pointing to the clock number 1, you would say 5 minutes. If the minute hand is pointing to the clock number 6, you would say 30 minutes. You can easily figure this out by counting by 5s around the clock. However, if the minute hand is in between two clock numbers, you have to count by 5s until you get to the nearest clock number, and then count up by ones to figure out how many minutes you have.

Take this as an example: Notice that the hour hand is between the 7 and the 8. To count the minutes, you would count each clock number—remember to count by fives! You should have counted 35 minutes.Students play a generalized version of connect four, gaining the chance to place a piece on the board by solving an algebraic equation.

Parameters: Level of difficulty of equations to solve and type of problem. Oct 10,  · How to find the angle between the hands of an analog clock at any given time?

## Secondary Maths Teaching Inspiration

Buy Painless Algebra (Painless Series) on plombier-nemours.com FREE SHIPPING on qualified orders. Find here an annotated list of problem solving websites and books, and a list of math contests. There are many fine resources for word problems on the net!

have personally checked & reviewed each website, to make sure it is truly useful. To solve this problem we need n, a 1, and a plombier-nemours.com this problem, n will be equal to 30 because we are being asked to find how many seats are in all 30 rows.

Most of the time when someone says “word problems” there is automatic panic. But word problems do not have to be the worst part of a math class.

Time Worksheets | Time Worksheets for Learning to Tell Time