A computer store has certain software on sale at 3 for $20.00, with a limit of 3 at the sale price. Additional

Mathematics

1 answer:

alexgriva [62]3 years ago

7 0

Answer:

a) y = 9.95(x-3) + 20.00

b) Cost of 5 software packages = $39.90

Step-by-step explanation:

Given that:

Cost of 3 software at sale = $20

Cost of regular = $9.95

Let,

x be the number of software purchased.

We will subtract 3 from x because they cost $20.

y be the total cost.

y = 9.95(x-3)+ 20.00

Putting x=5 in expression

y = 9.95(5-3) + 20.00

y = 2(9.95) + 20.00

y = 19.90 + 20.00

y = $39.90

Hence,

a) y = 9.95(x-3) + 20.00

b) Cost of 5 software packages = $39.90

You might be interested in

A box contains 24 transistors,4 of which are defective. If 4 are sold at random,find the following probabilities. i. Exactly 2 a

zavuch27 [327]

SOLUTION

This is a binomial probability. For i, we will apply the Binomial probability formula

i. Exactly 2 are defective

Using the formula, we have

$\begin{gathered} P_x=^nC_x\left(p^x\right?\left(q^{n-x}\right) \\ Where\text{ } \\ P_x=binomial\text{ probability} \\ x=number\text{ of times for a specific outcome with n trials =2} \\ p=\text{ probability of success = }\frac{4}{24}=\frac{1}{6} \\ q=probability\text{ of failure =1-}\frac{1}{6}=\frac{5}{6} \\ ^nC_x=\text{ number of combinations = }^4C_2 \\ n=\text{ number of trials = 4} \end{gathered}$

Note that I made the probability of being defective as the probability of success = p

and probability of none defective as probability of failure = q

Exactly 2 are defective becomes the binomial probability

$\begin{gathered} P_x=^4C_2\times\lparen\frac{1}{6})^2\times\lparen\frac{5}{6})^{4-2} \\ P_x=6\times\frac{1}{36}\times\frac{25}{36} \\ P_x=\frac{25}{216} \\ =0.1157 \end{gathered}$

Hence the answer is 0.1157

(ii) None is defective becomes