can you help me with 5th grade math?

Question

(4.3) (3.59)

Answer 1

This is straight multiplication where you ignore the decimals until the end. THEN count over three place from the right and put the decimal in the answer.

(4.3) (3.59) = 15.437

done!

Answer 2

OK - this look like you want to multiply the two decimals.

4.3 * 3.59 = 15.437

Here are a few tips to help you:

1. You know that the first number is a little more than 4 and the second number is more than 3 so your answer has to be more than 4 x3 = 12

2. The second number's decimal is more than .5 so it is a little more than 1/2. So now you know your answer has to be more than 4 x 3.5 = 14

3. You also know that the second number is less than 4 so you know your answer must be less than 4x4 = 16.

So if you know these three items just by looking at the problem, you can see that our answer is probably pretty close.

Hope that helps.

Answer 3

359 x 43 = 15437 Easy calcuator math. Now, for the short cut:

You had 1 decimal point moved in your first answer (4.3 to 43) and two in your second (3.59 became 359), so move the decimal point in three from the right:

15.437

In base 10, you can do this short cut every time.

Answer 4

Yes indeed I certainly can. This is just a multiplication problem. Ignore the decimals for now.

359
x
43
_____

15437

Then count up ALL the decimals. In this case, there is one in 4.3 and two in 3.59. Count over 3 decimal places in your final answer, and you get:
15.437!!!!!!