A lot of laptop computers contain 20 good ones and 3 defective ones. If two are selected and tested, find the probability that at least one will be defective.

Step-by-step explanation:

Given : Number of good laptops =20

Number of defective ones=3

Total laptops =23

If 2 laptops were selected, then the probability that none of them was defective would be =

The probability that at least one will be defective= 1- P(none of them is defective)

Hence,  the probability that at least one will be defective.

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places

it is a secret for it not to be compromised sorry

step-by-step explanation: