To find the mid segment, it is half of the sum of the bases
for number 13 it's 7+13=20 20/2=10
number 14 it's 12+9=21 21/2=10.5
number 15 it's 22+18=40 40/2=20
Answer:
Two sequences have the formulae 3n-1 and 7n+2 . A new sequences is formed by the number which appear in both of these sequences.
Step-by-step explanation:
There are 10 juice boxes in the cooler altogether.
2 of them are grape.
The first time Jill pulls one out with her eyes closed,
the probability that it's a grape is
2 / 10 .
If that try is successful, then there are 9 boxes left in the cooler,
and one of them is grape.
If she already has one grape, and reaches in again with her eyes
closed, the probability of pulling out the second grape is
1 / 9 .
The probability of both events happening in two tries is
(2/10) x (1/9) = 2/90 = 1/45 = (2 and 2/9) percent .
