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sattari [20]
4 years ago
13

Radium-226 is a metal with a half-life of 1600 years. If you start with 1 kilogram of radium-226, how much will remain after 20,

000 years?
Mathematics
1 answer:
erica [24]4 years ago
6 0
Ending Amount = Beginning Amount / 2^n 
where 'n' = # of half lives
n = 20,000 / 1,600 = 12.5 half-lives

Ending Amount = 1 kg / 2^12.5
Ending Amount = 1 kg / <span> <span> <span> 5,792.6
</span></span></span>Ending Amount = <span> <span> <span> 0.00017263 kilograms = </span></span></span><span>0.17263 grams


</span>
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Mary wants to find the area of the rectangle below.
jek_recluse [69]
So first find the area
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area=5/6 times 1/6
5/6 times 1/6=5/36
area=5/36 square units

tile=side legnth 1/6
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1/6 times 1/6=1/36
we must find how many times 1/36 goes into 5/36
divide 5/36 by 1/36
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4 0
3 years ago
Wayne took 2 hours to cover 1/3 of a trip. He covered the remaining 60 miles in 2 hours. Find his average speed for the entire t
faust18 [17]
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3 0
3 years ago
A Cab charges $1.75 for the flat fee and $0.25 for each mile. Write and solve an inequality to determine how many miles Eddies c
NemiM [27]
1.75 + 0.25x ≤ 15
where x is equal the number of miles.

The key to solving an inequality is just temporarily making the ≤ symbol a =. Then solve for x like any other algebraic equation. Once you find the value of x, you will have solved the inequality. Make sure to add back the ≤ when you are done. 

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add back the ≤
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4 0
4 years ago
A fish tank has 35 gallons of water in it, but suddenly starts leaking. Water is leaking from the tank at a rate of 1/4 gallon p
Norma-Jean [14]

Answer:

35 - m

Step-by-step explanation:

A tank containing 35 gallons of water is leaking at a rate of gallon per minute.

"m" represents the number of minutes spent

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Number of gallons of water left = 35 gallons – number of minutes spent  rate of leakage.

Number of gallons of water left = 35 gallons – m minutes  1 gallons per minute

8 0
3 years ago
2 + 2 - 1<br><br>I really need help​
shutvik [7]

Answer:

3

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2+2=4 because if you separate 2 and 2, you get four ones, therefore it's four

Now that you have four, subtract 1

And you got 3

5 0
3 years ago
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