The sum of two numbers is 8. Two times the larger number plus four times the smaller number is 8. Find the numbers.

12 and -4

Step-by-step explanation:

Assume the larger number is x and the smaller one is y.

In that case the relevant simultaneous equations are:

x + y = 8

2x + 4y = 8

Use substitution to find relative value of y:

x + y = 8

y = 8 - x

Use to solve equation:

2x + 4y = 8

2x + 4(8 - x) = 8

2x + 32 - 4x = 8

2x  - 4x= 8 - 32

-2x = -24

x = -24 / -2

x = 12

y = 8 - x

= 8 - 12

= -4

∞ this is your sign

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.