The "k" value should have units and should be negative.
k = -.07 / seconds
Half-Life = ln (.5) / k
Half-Life = ln (.5) / -.07
Half-Life = -.693147 / -.07
Half-Life = 9.9 seconds
(actually, wkpedia says half-life of Krypton 91 is 8.57 seconds)
elapsed time = half-life * log (bgng amt / end amt) / log (2)
elapsed time = 9.9 * log (100 / 10) / 0.30102999566
elapsed time = 9.9 * 1 / 0.30102999566
<span><span>elapsed time = 9.9 * 3.3219280949
</span>
</span><span><span><span>elapsed time = 32.8870881395
</span>
</span>
</span>
<span>elapsed time = 32.89 seconds (rounded)
Source:
http://www.1728.org/halflife.htm
</span>
X + (x + 1) + (x + 2) = 126
3x = 123
x = 41
So the sides are 41, 42 and 43
Answer: 2 × 3 × 3 or we can also write them as 2 × 32, where 2 and 3 both are prime numbers.
Example question: There are 38 students in a baseball club. The coach needs to split them up into equal groups of 4. How many groups can be made? How many kids are left over?
Answer: You would make groups of 4 to get your quotient (9). Then whatever is NOT in a group is your left over.