Answer:
negative
Step-by-step explanation:
calculating the z score by subtracting the mean and dividing by the standard deviation
(55-70)/10= -1.5
It's negative
Answer:
-5
Step-by-step explanation:
2x-6
2(.5)-6
1-6
-5
Answer:
11
Step-by-step explanation:
you just divide it
Its a simultaneous equation:
lets make "x" the used games and "y" the new ones
4x + 2y = 84
6x + y = 78. (multiply this by 2 to cancel out y)
12x + 2y = 156
so now we subtract them:
12x - 4x = 156 - 84
x = 9
used games cost $9
new games cost 78 - 6(9) = $24
Janet has $120 but she already bought 3 NEW games so:
120 - 3(24) = $48 left
48/9 = how many used ones she can buy = 5. something
she can buy 5 used