One card is selected at random from a deck of cards. Determine the probability that the card selected is a card greater than 3 and less than 8.

4/13

Step-by-step explanation:

Count all cards that are 4, 5, 6, and 7 (each of 4 different suits) so the number of cards that is greater than 3 and less than 8 = 4(4) = 16.

There are 52 cards in a standard deck of cards.

P(greater than 3 and less than 8)

= 16/52

= 4/13

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for