About 92 days are taken for 90 % of the material to <em>decay</em>.
The mass of radioisotopes (
), measured in milligrams, decreases exponentially in time (
), measured in days. The model that represents such decrease is described below:
(1)
Where:
- Initial mass, in milligrams.
- Current mass, in milligrams.
- Time constant, in days.
In addition, the time constant is defined in terms of half-life (
), in days:
(2)
If we know that 
, 
and 
, then the time required for decaying is:
About 92 days are taken for 90 % of the material to <em>decay</em>.
We kindly invite to check this question on half-life: brainly.com/question/24710827
6 bills in the deposit were $10 bills.
<u>Step-by-step explanation:</u>
The total number of bills he gave the teller = 24 bills
x + y = 24 ------------(1)
Let,
x be the number of $5 bills.
y be the number of $10 bills.
The total bank deposit made using $5 and $10 bills are $150.
<u>He deposits $5 bills and $10 bills. So, the equation can be framed as :
</u>
5x + 10y = 150 --------(2)
The question is asked for how many $10 bills were in the deposit,
Here 'y' is the number of $10 bills.
<u>To solve for y value :
</u>
The eq(1) must be multiplied by 5 and subtract eq(2) from eq(1),
5x + 5y = 120
-(<u>5x + 10y = 150</u>)
<u>-5y = -30 </u>
⇒ y = 30/5
⇒ y = 6
Therefore, there were 6 bills in the deposit that are $10 bills.
Calculate rank percentile in Excel
To calculate the rank percentile of a list data, you can use a formula. Select a blank cell that you will place the rank percentile at, type this formula =RANK. EQ(B2,$B$2:$B$9,1)/COUNT($B$2:$B$9), press Enter key and drag fill handle down to calculate all rank percentiles.
Here. I drew a triangle just for this problem. :) You can find it in attachments.
To find the angle, we must use the sine function. To find the angle, we must know the sine of the angle first. The formula for the angle we are trying to find is:
(Forgot to mention,
let the angle = x)
=
Knowing this, we can now derive that:
Using our scientific calculators, we find that:
°
Which is our final answer. You may round accordingly.
Thank you, and I hope that helped. :)
Answer:
1 x 0.28 works, along with 5 x 0.056.
