Identify the property used in each step. 12.2 + 18.6 + -4.3 + (-18.6) 12.2 + -4.3 + 18.6 + (-18.6) = (property?) 12.2 + -4.3 + [18.6 + (-18.6)] = (property?) 12.2 + -4.3 + (0) = (property?) 12.2 + -4.3 7.9

Drag the tiles to the correct boxes to complete the pairs. not all tiles will be used. the heights of the girls in an advanced swimming course are 55, 60, 59, 52, 65, 66, 62, and 65 inches. match the measures of this data with their values.

The number of chocolate chips in an 18-ounce bag of chocolate chip cookies is approximately normally distributed with a mean of 1252 chips and standard deviation 129 chips. (a) what is the probability that a randomly selected bag contains between 1100 and 1500 chocolate chips, inclusive? (b) what is the probability that a randomly selected bag contains fewer than 1125 chocolate chips? (c) what proportion of bags contains more than 1225 chocolate chips? (d) what is the percentile rank of a bag that contains 1425 chocolate chips?

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?