Cancer Math Challenge

You can measure the amount of all inorganic components in seawater when you know the amount of any one component.

Seawater's Inorganic Salt Components

Chloride

Cl-

55.04%

Sodium

NA+

30.61%

Sulfate

SO4--

7.68%

Magnesium

Mg++

3.69%

Calcium

Ca++

1.16%

Potassium

K+

1.16%

Carbonic Acid

HCO3-

0.41%

Bromine

Br-

0.19%

Boric Acid

H3Bo3

0.07%

Strontium

Sr++

0.04%

TOTAL   99.28%

MATH CHALLENGE

Write Your Name:

What are percentages? Percentages are numbers that express the parts of something on a 100 scale. Think of the number 100 as expressing the total amount of anything.

For example, if there are five people in your family, and they were all in the kitchen, you would say that 100% of your family was in the kitchen. Wow! What are you cooking?

If only your sister and your brother were in the kitchen, your could say that only 40% of your family was there. How do you figure that?

5 people =100% of your family. -->> Divide 100 by 5. -->> 100/5=20.

In other words, each person in your family represents 20% of the whole.

(20%+20%+20%+20%+20%=100% of your family)

If there are 3 people in the kitchen, what percentage of your family is there? (Write in the boxes.)

Only you are in the kitchen. What percentage of your family is there?

LET'S SOLVE SOME PROBLEMS. TAKE YOUR TIME. ASK FOR HELP IF YOU NEED IT. READ THE IDEAS ABOVE. HAVE FUN.

FILL IN THE BOXES WITH YOUR ANSWERS. PRINT THIS PAGE AND PLACE IT IN YOUR FOLDER. WE'LL SOLVE THE FIRST ONE TOGETHER.

SITUATION: You are reading the newspaper ads for used cars. You notice that one car lot is selling its cars at 15% off of their marked prices today only! Hmmmm... can you afford any of their cars? How much would each of the following cars cost at 15% off? How much would you save on each one if you bought it today?

Let's do the first one together.

Car #1: Marked Price: $ 7,500.00. The total amount (100%) is $7,500.00.

Step 1. To find out the percentage amount in dollars, multiply the total amount by the percentage. Express the percentage amount in decimals (15%=.15)

$7,500 X .15 = $1,125

15% of $7,500 is $1,125. So you would SAVE $1,125!

Step 2: What would you pay? Deduct the amount you save from the marked price.

$7,500 (marked price) - $1,125 (the amount you saved)= $6,375.00.

You would pay $6,375.00!

Car #2: Marked Price: $ 6,500.00

You would save .

You would pay .

Car #3: Marked Price: $ 4,300.00

You would save .

You would pay .

Car #4: Marked Price: $ 3,250.00

You would save .

You would pay .

EXTRA CHALLENGE!

What would you do to find the salinity in half a kilogram (kg) of ocean water? To move from one line to another, press the TAB key on your keyboard or CLICK the next line with your mouse.

PRINT THIS PAGE AND PLACE IT IN YOUR FOLDER.

ADDITIONAL PRACTICE: Visit http://www.ksellars.demon.co.uk/Oassign1.html and complete the exercises on measuring ocean depths.

Also...

http://www.ksellars.demon.co.uk/marine_animal_project.htm

Write Your Name:

Click on the arrow to return to the Main Page