A i did this problem before with another user
Answer:
25 mm
Step-by-step explanation:
Set up a proportion where x is the number of millimeters for 160 kilometers
= 
Cross multiply and solve for x:
32x = 800
x = 25
So, 25 millimeters represent 160 kilometers
Step-by-step explanation:
The number of people to paint the bridge is inversely proportional to the number of hours it takes.
(If there are more people, it will take less time etc.)
9 people can paint the bridge in 5 hours.
=> 2 people can paint the bridge in 5 * (9/2) = 22.5 hours.
Answer:
t = 2.52 seconds
Step-by-step explanation:
h=139-15t-16t^2
We want to know when the ball hits the ground
That would be when h=0
0 = 139-15t-16t^2
We can use the quadratic formula to find t
t = -b ± sqrt(b^2-4ac)
----------------------
2a
where a = -16 b = -15 and c = 139
t = -(-15) ± sqrt((-15)^2-4(-16)139)
----------------------
2(-16)
t = (15) ± sqrt(225+8896)
----------------------
-32
t = (15) ± sqrt(9121)
----------------------
-32
t = 15+ sqrt(9121) t = 15- sqrt(9121)
-------------------- or -------------------
-32 -32
-3.453247707 or 2.515747707
Since time cannot be negative
2.515747707
Round to the nearest hundredth
t = 2.52 seconds
Whats the problem? i cant solve it w/o the problem doll
