Answer: -7.7
Step-by-step explanation: -2.2(3.5) = ?
First lets estimate. -2.2 rounds down to -2 and 3.5 rounds up to 4, because of the rule of rounding 5 and up rounds to the next highest number, 4 and down rounds down to the next lowest number. Now we are going to multiply the -2 by the 4 = -8. Now that we have our estimate we can solve the problem. For this problem we are going to multiply these numbers as whole numbers, how we do that is by multiplying -22 by 35, by doing this we have to take out the decimal points but we need to remember how many decimal places there were so we can put them back when we are done. To count how many decimal places there were we take the decimal point and move it to the left until its in front of the number.
In this case -2.2 has 1 decimal place and so does 3.5. So, remember that we have 2 decimal places.
-22(35) = -750. It is negative because when you multiply a number by a negative the answer is negative, but when you multiply a negative by another negative the answer is positive.
To turn this back into a decimal number we will need those 2 decimal places. We are going to put the decimal place 2 spaces to the right of the number so it will look like this: -7.70 now that it is a decimal we don't need the 0 so we take it off and get -7.7 which is close to our estimate of -8 so our answer is reasonable. Hope this helps.