one question how do you know how many decimal places to put in the product?

Answer 1

add the decimal places in both operands and use this many in the product.

Answer 2

Let's say you are multiplying 2.5 by 2.5. The answer will be 6.25 with 2 decimal places. Why? Because there's one decimal place in the first number and also one in the second, i.e, 1+1=2 decimal places.

Suppose you are multiplying 12.34 by 15.652. The answer will be 193.14568 with 5 decimal places, since the first number has 2 decimal places and the second one has 3, i.e., 2+3=5 decimal places.

I hope I understood your question correctly.

Answer 3

Count the place of the decimal point from right to left.
Ex: 2.45 In this the decimal point is 2 places towards left.
Ex: 1.001 In this the decimal point is 3 places towards left.
Now multiply 245 * 1001 = 245245
Sum up the decimal places of both the numbers in above examples, that is 2+3 = 5 places.
Place the decimal point at 5 places from right to left of the product.
Hence 2.45 *1.001 = 2.45245

Answer 4

it depends on the number you are multiplying with!

example: 1.0010 * 9.098 = 9.107098.
The first number has three decimals( the last 0 has no value) and the second number also has 3 decimals. so 3+3=6 decimals for the answer.

Answer 5

Well pretty simple or more complicated depending on the type of math your doing. Simple way like if you’re multiplying two numbers like this. 42.08 times 103.666 = 4392.26528 just count the number of digits before the decimal point from right to left in both of the numbers your multiplying then add the numbers. In this case two plus three is five. In your answer count five numbers from right to left and place your decimal point in front or to the left of the fifth digit. You can do the same thing if your multiplying three or more numbers. If this is not clear ya can email me at [e-mail]
2.1234567X25.987654321=55.1836586852114007

Answer 6

Well, if you have enough room and patience, you can put as many as you so desire. Asumming that these prerequisites aren't met, you can either end the decimal with a ... or you can put a horizontal line above any number(s) that repeat forever (the second one only works if the decimal repeats).

Answer 7

It depends on how large(small) the answer.
...jj

Answer 8

2000000000000000000000000000000000000000000000000000000