Answer:Gary-18 brother-10
Step-by-step explanatiation:Gary=8 years+ brother's years
6 years ago :
Gary=3×brother's years
So:
1st case:brother=1 year,gary=3 years=>after 6 years brother=7 years,gary=9 years (NO)
2nd case:brother=2years,gary=6 years=>after 6 years brother=8 years,gary=12 (no)
3rd case:brother=3 years,gary=9 years=>after 6 years:brother=9 yrs, gary=15 yrs(no)
4th case:brother=4 yrs,gary=12 yrs=>after 6 years: brother=10 years,gary=18 years (This is the one)
Answer:What is the 11th term of this geometric sequence 5, 20, 80, 320? In the present GP, a = 5 and r = 20/5 = 4. So the 11th term of the GP = ar^10 = 5*4^10 = 5242880.
Step-by-step explanation:
Answer:
d. 13.5, 20.25
Step-by-step explanation:
An exponential function is monotonic and does not change sign. On this basis alone, the first three choices can be eliminated.
The common ratio is 6/4 = 3/2.
The term in the sequence after 9 is 9·(3/2) = 27/2 = 13.5.
The term in the sequence after 27/2 is (27/2)·(3/2) = 81/4 = 20.25.
This is a freefall problem with an acceleration of -10m/s (a poor approximation of g :P)
a=g
v=gt+v0
h=gt^2/2+v0t+h0 where v0 is initial velocity and h0 is initial height.
You have:
h=-5t^2+10t+3
Since h0=3, the springboard is 3 meters above the water.
...
The diver hits the water when h=0.
5t^2-10t-3=0
Using the quadratic equation for simplicity:
t=(10±√160)/10
t=(10±4√10)/10 seconds, since t>0
t≈2.26 seconds (to nearest hundredth of a second)
So the diver hits the water about 2.26 seconds after (s)he leaves the springboard.