You have 12 CDs, but only have time to listen to two of them. How many combinations of CDs do you have to choose from?

1 answer:

7 0

Total number of CDs = 12
Number of CDs that can be selected at once = 2

Selecting 2 CDs from 12 means combination of 12 objects taken 2 at a time. This can be calculated by 12C2.

$12C2 = \frac{12!}{2!*(12-2)!} \\ \\ 
12C2= \frac{12!}{2!*10!} \\ \\ 
12C2= \frac{12*11}{2} \\ \\ 
12C2=66$

This means, we have 66 possible combinations to choose from

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A shopper paid $2.52 for 4.5 pounds of potatoes,$7.75 for 2.5 pounds of broccoli,and $2.45 for 2.5 pounds of pears.What is the u

Sidana [21]

Answer:

Step-by-step explanation:

A shopper paid $2.52 for 4.5 pounds of potatoes. This means that the unit price for each potato would be

2.52/4.5 = 0.55556

Approximately $0.6 per pound.

The shopper paid $7.75 for 2.5 pounds of broccoli. This means that the unit price for each broccoli would be

7.75/2.5 = $3.1 per pound.

The shopper paid $2.45 for 2.5 pounds of pears. This means that the unit price for each pear would be

2.45/2.5 = $0.98 per pound

6 0

3 years ago

Compute 5e2 - 4g + 7 where e = 4 and g = 6 ?

Elza [17]

The value of expression is 63 when e = 4 and g = 6

Solution:

Given expression is:

$5e^2-4g+7$

We have to solve the expression

Given that e = 4 and g = 6

Substitute e = 4 and g = 6 in given expression

$\rightarrow 5(4)^2 -4(6) + 7\\\\Simplify\ the\ above\ equation\\\\\rightarrow 5(16) -24 + 7\\\\\rightarrow 80-24+7\\\\Simplify\\\\\rightarrow 56+7=63$