Answer:
There were 10 flies originally
Step-by-step explanation:
Since we have an exponential growth, we will be having a constant percentage of increase and we can set up the increase at any day using the following equation;
V = I(1+r)^d
where V is the number of flies on a particular day
I is the initial number of flies
r is the constant increase in percentage
and d is the number of days.
So we have for the second day;
60 = I(1+r)^2 ••••••(i)
For the fourth day, we have;
360 = I(1+r)^4 ••••••••(ii)
divide equation ii by i; we have;
360/60 = (1+r)^4/(1+r)^2
6 = (1+r)^2
(√6)^2 = (1+r)^2
1 + r = √6
r = √6 - 1
So we can substitute the value of r in any of the equations to get I which is the initial number of flies
Let’s use equation 1
60 = I(1 + r)^2
60 = I(1 + √6 -1)^2
60 = I(√6)^2
60 = 6I
I = 60/6
I = 10 flies
Answer:
A
Step-by-step explanation:
They are basically wanting the value of x.
These are 2 secant lines drawn. Secant Line is a line that intersects the circle at 2 points.
To solve this, we have to use secant-secant theorem.
Secant-Secant Power Theorem tells us that if 2 secant lines are drawn from external point (here, E) to a circle, then, product of measure of one secant's external part and total secant is equal to other secants external part and whole secant.
In algebra, that is:

Let's multiply and find the value of x:

Hence, the correct answer choice is A
He will spend 80% of his money