Answer: -3.125 or -25/8
Step-by-step explanation:
I do not know what has been covered in your class, but the "x" appears to be multiplication here.
It would be best to convert into all decimals or all fractions.
For all fractions (I think is easiest):
-2.5 is -2 1/2 = -5/2 and then 1 1/4 = 5/4 (need improper fractions to multiply, then multiply straight across)
Then take -5/2 * 5/4 = -25/8 (multiply fractions by multiplying numerators together, then denominators together). If you need this as a mixed number, -25/8 is -3 1/8
For all decimals:
-2.5 is already as a decimal, then 1 1/4 = 1.25
So then multiply:
1.25 (I put 1.25 first because it has more digits)
x -2.5 (note- multiplying a positive by a negative gives you a negative)
6 2 5 (multiply 5x5 first, giving 25, so place 5 and carry the 2,
then multply 5x2 = 10 plus the 2 carried is 12, carry that 1
then 5x1 = 5 plus the 1 carried is 6)
+ 2 5 0 0 (0 placeholder first, now multiply the 2 by each digit of 1.25,
2x5 = 10, carry the 1, then multiply 2x2 = 4 plus the 1 carried
is 5, then multiply the -2 by the 1 , -2x1 = -2)
Now add the 625 + 2500 = 3125, there were 3 digits after the decimal originally, so move decimal back 3 places, giving 3.125. Finally, the answer is negative because you multiplied a negative number with a positive one. SO the final answer is -3.125 (also equal to the -25/8)
