Here is the set up:
Let x and y be the two numbers with x the smaller and y the larger number.
x + y = 66
2x = y + 15
We have two equations in two unknowns.
Take it from here.
Options :
A. The initial number of bacteria is 7.
B. The initial of bacteria decreases at a rate of 93% each day.
C. The number of bacteria increases at a rate of 7% each day.
D. The number of bacteria at the end of one day is 360.
Answer:
C. The number of bacteria increases at a rate of 7% each day.
Step-by-step explanation:
Given the function :
f(x)=360(1.07)^x ; Number of bacteria in sample at the end of x days :
The function above represents an exponential growth function :
With the general form ; Ab^x
Where A = initial amount ;
b = growth rate
x = time
For the function :
A = initial amount of bacteria = 360
b = growth rate = (1 + r) = 1.07
If ; (1 + r) = 1.07 ; we can solve for r to obtain the daily growth rate ;
1 + r = 1.07
r = 1.07 - 1
r = 0.07
r as a percentage ;
0.07 * 100% = 7%
Answer:
<em>4.7 years</em>
Step-by-step explanation:
Distance of planet from Earth = 1.3 parsec
We know that 1 parsec = 3.26 light years
And a light year is the distance traveled by light in time period of 1 year.
So, Distance of planet from Earth = 1.3 
3.26 = 4.24 light years
Given that, the person travels at a speed equal to 90% of the light speed.
To travel to the planet from Earth, Light takes 4.24 years.
To travel the distance 
, at a speed 
light takes time of 4.24 years.
To travel the distance , at a speed 
, the person takes time:
So, the twin on Earth ages by <em>4.7 years.</em>
In order to solve the given expression follow these steps:
1. Take the square roots on both sides in order to get rid of the power on the left side:
√(x-5)² = ±√3
x - 5 = ±√3
2. add 5 on both sides:
x-5 + 5 = 5 ±√3
x = 5 ±√3
Then, the solution is x = 5 ±√3
Answer:
D Multiply equation B by 5 and equation A by 4 and add the results together
