We rewrite the equation:
y = y0 * e ^ (- 0.0002 * t)
In this equation:
I = represents the initial amount of the isotope
We have then:
89% of the isotope left:
0.89 * y0 = y0 * e ^ (- 0.0002 * t)
We clear the time:
e ^ (- 0.0002 * t) = 0.89
Ln (e ^ (- 0.0002 * t)) = Ln (0.89)
-0.0002 * t = Ln (0.89)
t = Ln (0.89) / (- 0.0002)
t = 582.6690813
round to the nearest year:
t = 583 years
Answer:
There will be 89% of the isotope left in about:
t = 583 years
Answer: $200
Explanation:
The employee pays $172.50 and he got 25% employee discount.
If the cost is $100, he pays $(100 - 25) = $75.
So, employee pays =
100
75
⋅
172.50
= $230.00.
Again, price was increased by 15% last year. So whose cost is $100
is sold by $(100+15) = $115.
When sell price is $115, then cost price is $100. Then,
when sell price is $230, then cost price is
100
115
⋅
230
= $200.
Answer:

Step-by-step explanation:
Given

Required
Determine 

Open bracket

Equate the equation to 0

Express 3 as 1 + 1 + 1

Collect like terms

Group each terms

Factorize (starting with the first bracket)












Express 0 as 0 + 0 + 0

By comparison



Solving for 
Take square root of both sides

Add 1 to both sides


Solving for 
Take square root of both sides

Subtract 1 from both sides


Solving for 
Take square root of both sides

Subtract 1 from both sides


Substitute the values of a, b and c in 



This is what I got I dont know if It should be an equation but that's all i can get to, gl
Angela purchased 4 casual shirts and 6 dressy shirts.
$25 × 6 = $150
$18 × 4 = $72
$150 + $72 = $222
hope this helped :)