2 1/3 + 3 1/4 as a fraction

Step-by-step explanation:

convert both mixed fractions to improper fractions first

2 1/3 = 7/3    3 1/4 = 13/4

(cross multiplication method, to make both fractions have the same denominator)

7/3 + 13/4

7/3 × 4/4 = 28/12

13/4 × 3/3 = 39/12

28/12 + 39/12 = 67/12 (just add, denominator will remain the same)

67/12 (simplify)

67/12 = 5 7/12 (simplified)

d. vertex

step-by-step explanation:

85.560%

step-by-step explanation:

conditional probability is defined as:

p(a|b) = p(a∩b) / p(b)

in other words, the probability that a occurs, given that b has occurred = the probability that both a and b occur / the probability that b occurs.

in this example:

p(turns 64 | turns 44) = p(turns 64 & turns 44) / p(turns 44).

if someone turns 64, they must have already turned 44, so:

p(turns 64 | turns 44) = p(turns 64) / p(turns 44)

on page 42, we see that of the original 100,000, 94944 turn 44, and 81234 turn 64.   therefore:

p(turns 64 | turns 44) = 81234 / 94944

p(turns 64 | turns 44) = 0.85560