Answer:
40 mph
Step-by-step explanation:
If the speed increased by 20%, now the speed is 120% of the original speed.
48 mph is 120%, so dividing by 6 will get 8 which is 20%.
If 8 is 20%, you can multiply it by 5 to get 40, which is 100%. This means 40 mph is the original speed.
Hope this helps!
Answer:
y=1.003009+0.003453x
or
GPA=1.003009+0.003453(SAT Score)
Step-by-step explanation:
The least square regression equation can be written as
y=a+bx
In the given scenario y is the GPA and x is SAT score because GPA depends on SAT score.
SAT score (X) GPA (Y) X² XY
421 2.93 177241 1233.53
375 2.87 140625 1076.25
585 3.03 342225 1772.55
693 3.42 480249 2370.06
608 3.66 369664 2225.28
392 2.91 153664 1140.72
418 2.12 174724 886.16
484 2.5 234256 1210
725 3.24 525625 2349
506 1.97 256036 996.82
613 2.73 375769 1673.49
706 3.88 498436 2739.28
366 1.58 133956 578.28
sumx=6892
sumy=36.84
sumx²=3862470
sumxy=20251.42
n=13
b=9367.18/2712446
b=0.003453
a=ybar-b(xbar)
ybar=sum(y)/n
ybar=2.833846
xbar=sum(x)/n
xbar=530.1538
a=2.833846-0.003453*(530.1538)
a=1.003009
Thus, required regression equation is
y=1.003009+0.003453x.
The least-squares regression equation that shows the best relationship between GPA and the SAT score is
GPA=1.003009+0.003453(SAT Score)
You flip the signs when you are dividing by a negative value.
-2x+3>15
-2x>15-3
-2x>12
x<12/-2
x<-6
Now to test this
Try putting x in the original equation when it is -5.
-2(-5)+3>15
10+3>15
13>15
This is false because our answer says x is less than -6.
Now any value less than -6 will work so let's go with -7.
-2(-7)+3>15
14+3>15
17>15
This result is True.
Hope this helps out!