Yuto is correct because he isolated the variable correctly and reversed the inequality symbol.
x < 3
The person would have to leave the money in the bank for 7.8 years for it to reach 13,500 dollars.
Step-by-step explanation:
Step 1; First we must calculate how much interest is generated for a single year. The annual interest rate is 4.5% i.e. 4.5% of 10,000 dollars which equals 0.045 × 10,000 = 450 dollars a year. As the years pass, more and more will be put into the account due to interest.
Step 2; For there to be 13,500 dollars in the bank account we need to calculate how much money is added due to interest.
The money needed to be added through interest = 13,500 - 10,000 = 3,500 dollars.
So we need to determine how long it will take for the bank to add 3,500 dollars by adding 450 dollars a year.
The number of years to reach 13,500 dollars =
= 7.777 years. By rounding this value to the nearest tenth, we get 7.8 years.
If the radio active isotope has the half life of 24100 years, then the initial quantity is 2.16 grams
The half life in years = 24100
Consider the quantity of the radio active isotope remaining
y = 
When t = 1000 the y = 1.2
y = C/2 when t = 1599
Substitute the values in the equation
C/2 = 
Cancel the C in both side
1/2 = 
Here we have to apply ln to eliminate the e terms
ln (1/2) = 24100k
k = ln(1/2) / 24100
k = -2.87× 10^-5
To find the initial value we have to substitute the value of k and y in the equation
1.2 = Ce^{1000 × -2.87× 10^-5}
C = 1.2 / e^(-0.0287)
C = 2.16 gram
Hence, the initial quantity of the radioactive isotope is 2.16 gram
Learn more about half life here
brainly.com/question/4318844
#SPJ4