Answer:
?
Step-by-step explanation:
Answer:
11-2 or 9
Step-by-step explanation:
Answer:
To determine what is the difference between "6 + A" and "6 x A", the logic of the proposed mathematical operations must be explained:
In "6 + A", the value A is added to the initial value 6. Thus, for example, if A were worth 10, to the initial value 6 10 units are added, with which the final value is 16.
In contrast, in "6 x A", the initial value 6 is multiplied by as many times as the value A indicates. Therefore, continuing with the value of A as 10, in this case 6 would be multiplied by 10 times, giving a final value of 60.
The answer is 28 years
At = A0 * e^(-k * t)
At = 12 g
A0 = 15 g
k = 7.9 × 10^-3 = 0.0079
t = ?
12 = 15 * e^(-0.0079 * t)
12/15 = e^(-0.0079 * t)
0.8 = e^(-0.0079 * t)
Logarithm both sides (because ln(e) = 1:
ln(0.8) = ln(e^(-0.0079 * t))
ln(0.8) = (-0.0079 * t) * ln(e)
-0.223 = -0.0079 * t
t = -0.223 / -0.0079
t = 28.23
t ≈ 28 years