How many pairs of whole numbers have a sum of 40

    Ok first you need to convert all the numbers into one way which can be a percent, fraction or decimal so then it's easy to compare them. I'm going put them in decimals then organize them in their original form, probably what the teacher wants anyway. Fractions can become decimals if the denominator is 100. Even in decimal there's deci which means 10, we in this world revolve around systems of 10. Use 20/20  for - 2/5 because 20 times 5 will get you to 100, and then divide -40 by 100 and get -0.4. With percents it's simplier because they're already are out of 100. See when trying to move a percent back into a decimal just move the place value two times for every 0 in 100 ( you get -0.7 ) . Do the same thing with 0.96%. Finally the greater the number as a positive the greater value, while as a negative the greater the number the lesser the value. Using all this you finish with a sequence from the least to greatest. -70%, -2/5, 0.96%, 0.34.