Friday, October 18, 2019

Notes for Homework 8, due Mon., Oct. 21

Notes for conversion from metric to customary and vice versa

Changing Celsius to Fahrenheit

F = 9/5 C + 32

Changing Fahrenheit to Celsius

C = 5/9(F - 32)

Wednesday, September 18, 2019

Notes for Homework 5, due September 23

Notes on the Richter scale and the bel/decibel system for measuring sound

Notes on Venn diagrams

We will have three sets.

U is the universe, all the things that we will discuss.

A and B are the subsets.

The universe is the rectangle, A and B are the two ovals. A on the left and B on the right.

Example. Let the universe be U = {a, b, c, d, e, f, g}

A = {b, e, a, d}
B = {f, a, c, e}

a and e are in the middle sliver, while b and d are in the left oval and f and c are in the right oval.  The letter g isn't in either list, so it goes outside the circles.

Sorry the picture is hard to read.




Friday, April 26, 2019

Notes for Homework 10, due Mon. April 29 NOT ACCEPTED LATE

Notes on converting from metric to customary and vice versa

Changing Celsius to Fahrenheit

F = 9/5 C + 32

Changing Fahrenheit to Celsius

C = 5/9(F - 32)


 

Thursday, September 6, 2018

Notes for Homework 3

Notes for time given in decimal form

On Earth, a years is actually 365.2422 days. We make up the extra number by having a leap year every four years, with a few exceptions. How long is 0.2422 days in hours minutes and seconds?

Decimal days to hours, minutes and seconds:  To get the number of hours, we multiply 0.2422x24 = 5.8128 hours, we save the 5, then multiply the 0.8128 x 60 = 48.768, which means we now have 365 days, 5 hours, 48 minutes and some decimal part of a minute. 0.768x60 = 46.08 seconds, which means a year is 365 days, 5 hours, 48 minutes and 46.08 seconds.


A day on Saturn is 10.656 Earth hours. How do we change the decimal to hours, minutes and seconds?

Decimal hours to minutes and seconds: Multiply the decimal part by 60. In this case, .656 x 60 = 39.36 minutes. We save the 39 minutes and then multiply .36 x 60 = 21.6. This means the final answer is 10 hours, 39 minutes, 21.6 seconds.

Notes for scientific notation

Monday, April 30, 2018

Notes for Homework 11a, due May 1

Notes on the metric system vs. customary

Changing Celsius to Fahrenheit

F = 9/5 C + 32

Changing Fahrenheit to Celsius

C = 5/9(F - 32)

Wednesday, March 21, 2018

Notes for Homework 8, due March 28

Notes on determinants

A 2x2 matrix is an array of four numbers put in two rows and two columns, such as

| a c |
| b d |

The determinant of this matrix is ad - bc, the product of the main diagonal minus the product of the opposite diagonal. If you use Kramer's rule to solve a pair of simultaneous equations, you will need to know how to calculate determinants.

For example, let's consider the following set of equations.

3x - 2y = 7
2x + 4y = 12

As an augmented matrix , these equations become

|  3  -2  : 7 |
|  2   4  : 12|

Matrix_1 is

| 3 -2 |
| 2  4 |

The determinant is 3(4) - 2(-2) = 12 - -4 = 16
 

Matrix_x is

| 7 -2 |
| 12  4 |

The determinant is 7(4) - 12(-2) = 28 - -24 = 52
  Matrix_y is

| 3  7  |
| 2 12 |

The determinant is 3(12) - 2(7) = 36 - 14 = 22

From here, Kramer's rule then has x = 52/16 = 13/4 or 3 1/4. The value for y = 22/16 = 11/8 = 1 3/8
 
  Notes on solving simultaneous equations
 

Wednesday, November 22, 2017

Notes for Homework 12, due Mon., Nov 27



Notes on the metric system

Changing Celsius to Fahrenheit

F = 9/5 C + 32

Changing Fahrenheit to Celsius

C = 5/9(F - 32)




 

Wednesday, September 6, 2017

Notes for Homework 3, due MONDAY, SEPT. 11


Notes for decimal part of a day to hours, minutes and seconds.

Notes for scientific notation

Fractional part of a day


A year is defined by how long it takes a planet to make a single orbit around the sun. An Earth year is 365.2422 days. To make up for the decimal part we have a leap year every four years and skip the leap year if the number of the year is divisible by 100. This means we had leap years in 2004, 2008, 2012 and 2016, but we did not have one in 2000. What this lesson is about is to take the decimal part of this time and turn it onto hours, minutes and seconds.

Step 1. Multiply the decimal part by 24 to get the number of hours.
In this case, .2422 x 24 = 5.8128, which means 5.8128 hours.

Step 2. If there is still a decimal part, multiply it by 60 to get the number of minutes. We know know a year is 365 days, 5 hours and some number of minutes. That number is 60 x .8128 = 48.768

Step 3. If there is still a decimal part, multiply it by 60 to get the number of seconds.
We know know a year is 365 days, 5 hours, 48 minutes and some number of seconds. That number is 60 x .768 = 46.08. In these problems, it is okay to round to the nearest tenth of a second, so the final answer is 365 days, 5 hours, 48 minutes and 46.1 seconds.

Let's do another example. A year on Venus is 224.65 Earth days.

Step 1. .65 x 60 = 15.6, so the year on Venus is 224 days, 15.6 hours.

Step 2. 60 x .6 = 36, so that makes the year on Venus 224 days, 15 hours and 36 minutes. There is no more decimal part, so we don't have to add any seconds to our answer.

Here are two more practice problems. The answers are in the comments.

1. It takes Mercury 87.969 Earth days to travel around the sun. Write this number in days, hours, minutes and seconds.

2. It takes Mars 686.98 Earth days to travel around the sun. Write this number in days, hours, minutes and seconds.

Sunday, February 19, 2017

Thursday, November 10, 2016

Notes for Homework 10


I made a mistake labeling this homework assignment, calling it Homework 11. It is actually Homework 10 for the Tuesday-Thursday class.

These notes are from my statistics blog. The links contain a lot of information that we won't get to in Math for Liberal Arts. You should be able to search in your web browser for words like "mean", "median" and "mode", etc.

Notes on mean, median and mode

Notes on the five summary and outliers

Notes on raw scores to z-scores to proportions, also percentiles to z-scores to raw scores