In order to add 1 ⁄ 4 and 2 ⁄ 5, the denominators have to be the same. This means multiplying both the numerator and denominator of each fraction by the opposite fraction's denominator. 1 ⁄ 4 + 2 ⁄ 5

( 1 ⁄ 4 × 5 ⁄ 5 ) + ( 2 ⁄ 5 × 4 ⁄ 4 )

(1 × 5)/(4 × 5) + (2 × 4)/(5 × 4)

5 ⁄ 20 + 8 ⁄ 20 = 13 ⁄ 20

1/3 + 3/8 =

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?

Plz ( true - false) all triangles have interior angles whose measure sum to 90.

What is 100,000 times 1/100,000, using the standard method of multiplication? write the answer as 10 to a power.