Answer:
<h2>8/9</h2>
Step-by-step explanation:
9 in total 4 blue
4/9 x 2
8/9
Let x = total distance he covered
3x/4 by bus
1/2 . x/4 = x/8 by jogging
the remaining distance = x/8 by walking
thus x/8 = 800ft
x = 8 . 800 = 6400ft
The amount of the radioactive material in the vault after 140 years is 210 pounds
<h3>How to determine the amount</h3>
We have that the function is given as a model;
f(x) = 300(0.5)x/100
Where
- x = number of years of the vault = 140 years
- f(x) is the amount in pounds
Let's substitute the value of 'x' in the model
f(x) = 300(0.5)x/100
f(140) = 210 pounds
This mean that the function of 149 years would give an amount of 210 pounds rounded up to the nearest whole number.
Thus, the amount of the radioactive material in the vault after 140 years is 210 pounds
Learn more amount radioactive decay here:
brainly.com/question/11117468
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Answer: He will walk 2 1/4 miles in an hour