What is (6.31 × 10⁵) + (2.6 × 10⁴) as a standard form

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?

Which rule describes the composition of transformations that maps △abc to △a”b”c

Olivia is using 160 quilt squares to make a red, yellow, and blue quilt if 25% of the quilt are red and 30% are yellow how many quilt squares are blue