Answer:
The sum of the two numbers is 15
Step-by-step explanation:
Let the counting numbers be x and y.
Then we can write the following equations
x=4y.......1 (one is four times greater )
x(y)=36.....2 (the product of the two)
Putting equation 1 into equation 2, we get
4y(y)=36
Dividing through by 4,we get
Taking square root of both side, we obtain
y=3
Putting the value of y into equation , we get
x=4(3)=12
Hence the numbers are 3 and 12
Therefore the sum of the two numbers is 3+12=15
9514 1404 393
Answer:
a) 600
b) see below
c) 1.26 hours
Step-by-step explanation:
a) The value of y when x=0 is the coefficient of the exponential term:
y = 600·3^(-0) = 600·1 = 600
There were 600 atoms to start.
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b) see attached for a graph
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c) The graph shows 150 atoms at t = 1.26, about 1.26 hours after the start of time counting.
If you want to find that value algebraically, substitute for y and solve for x. Logarithms are involved.
150 = 600·3^(-x)
150/600 = 3^(-x)
log(1/4) = -x·log(3)
x = -log(1/4)/log(3) = log(4)/log(3) ≈ 1.2618595
After about 1.26 hours, there were 150 atoms.
