Hello.
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Nearest ones place - 4.27
Nearest tenths place - 4.3
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Hope it helps.
<h3>
Answer:</h3>
60 days
<h3>
Explanation:</h3>
Half-life is the amount of time it takes half of a substance to decay away.
Guess and Check
One method for solving half-life problems like this is to guess and check. To do this, we can continue to divide 475mg by 2 until we get to 30mg.
- 475 ÷ 2 = 237.5
- 237.5 ÷ 2 = 118.75
- 118.75 ÷ 2 = 59.375
- 59.375 ÷ 2 = 29.6875
As seen here, it takes approximately 4 half-lives for this sample of Ra-225 to decay to 30mg. Now, we can multiply 4 by the length of the half-life, 15 days.
Fractions
Another way to solve this is to use fractions.
- 16 is equivalent to
.
This means that it takes 4 half-lives for 475mg to decay to 30mg. Using the same method above, we can tell that 4 half-lives are 60 days.
Important Note
In this question, I rounded occasionally. So, not all of the values are exact, but they are all very close.
Answer:
junior reserves officers training corps
Answer:
Heat energy transferred in the form of waves is called Radiation.
Answer:
Amount to spend = $18.50
Purchased banana =$1.50
Apple Juice =$1.55
Gasoline $2.35
$1.50 + $1.55 = $3.05
18.50 - 3.05 = 15.45
1 Gallon of Gasoline = 2.35
Therefore,
2.35 x 6 = 14.1
15.35 - 14.1 = 1.25
To avoid exceeding budget, he can only buy
6 gallons of gasoline