Answer:
78
Step-by-step explanation:
10% = 6
⬇️ x3
30% = 18
⬇️ Add onto 60
60+18=78
H is 2t
h + t = 84
2t + t = 84
3t =84
t = 28
Thomas is 28 and huilan is 56
Answer:
(3,-3)
y= -3
x= 3
Step-by-step explanation:
5x+2y=9
2x-3y=15
solve the equation
x=9/5-2/5y
2x-3y=15
substitute the value of x into an equation
2(9/5-2/5y)-3y=15
distribute
18/5-4/5y-3y=15
subtract -4/5 to -3
18/5-19/5y=15
subtract 18/5 from both sides
-19/5=57/5
divide both sides by -19/5
y= -3
substitute the value of y into an equation
x=9/5-2/5(-3)
distribute
x=9/5+6/5
add 9/5 to 6/5
x=3
--------
(3,-3)
--------
Answer:
81.8%
Step-by-step explanation:
Mean = 
Standard deviation = 
Now we are supposed to find out what percent of the numbers fall between 35 and 50

Substitute the values

Now for P(35<x<50)
Substitute x = 35


Substitute x = 50


So, P(-1<z<2)
P(z<2)-P(z<-1)
=0.9772-0.1587
=0.8185
= 
=81.8%
Hence 81.8% percent of the numbers fall between 35 and 50
Answer is (A) because it is concave and it has 8 sides