SCIENTIFIC NOTATION HOMEWORK! HELP PLEASE!!!?

Question

I have a teacher who gave us four pages of scientific notation problems...well... here's the problem...

I know the 4.05 x 10 *4 {the four is post to be an exponent/power and I dont know to make the 4 into an exponent on the computer so the star tells you were it goes}

but...He/she never taught us how to do. (5.5 x 10*4 cm) x (1.4 x 10*4 cm) PLEASE HELP ME! My mom isn't good at math! PLEASE HELP!

Oh...it's 9th grade work and I'm not even in 9th grade yet.

But please tell me how to go through it...or some pointers to help me understand it! PLEASE!!!

I'm desperate...

thank you

Answer 1

(5.5 x 10*4 cm) x (1.4 x 10*4 cm)

Multiply the decimals in front, and add the exponents:

7.7 X 10*8 square cm

Answer 2

Scientific notation is just moving the decimal point. The exponent after the 10 tells you how many places to move the decimal, and in what direction. If the exponent is positive, move the decimal point to the right. If the exponent is negative, move it to the left. So in your first question, 4.05 x 10^4 (the ^ is the correct way to indicate an exponent, by the way), you will move the decimal in 4.05 four places to the right, giving you 4050.  When you are multiplying two numbers that have exponents, multiply the simple numbers and add the exponents. So (5.5 x 10^4) x (1.4 x 10^4) would be (5.5 x 1.4) x 10^8, or 7.7 x 10^8. If your teacher wants this written out, it would be 770,000,000.

If you are allowed to check your answers on a calculator, use the "e" or "EE" button to enter the "10^" - for your first question, you would type 4.05 EE 4 or 4.05 e 4.

Hope this helps.

Answer 3

good luck