.2 (simplified from 0.20)
2/10 (simplified from 20/100)
Answer:
85.5 minutes
Step-by-step explanation:
The amount of an element that will remain after time t can be expressed as a function of initial amount N0, time t, and half life th as;
Nt = N0 × e^(-λt)
Where;
Decay constant λ = ln(2)/th, substituting into the equation;
Nt = N0 × e^(-ln(2)t/th)
We need to make t the subject of formula;
Nt/N0 = e^(-ln(2)t/th)
ln(Nt/N0) = -ln(2)t/th
t = ln(Nt/N0) ÷ -ln(2)/th
Given;
Initial amount N0 = 760g
Final amount Nt = 11 g
Half life th = 14 minutes
the nearest tenth of a minute, would it take the element to decay to 11 grams can be derived using the formula;
t = ln(Nt/N0) ÷ -ln(2)/th
Substituting the given values;
t = ln(11/760) ÷ -ln(2)/14
t = 85.5 minutes
Let's say the width is (x) and the width is (x+12). The formula for a perimeter of a rectangle equals 2w + 2l, which would then for this problem be 100=2(x) + 2(x+12) which would distribute as 2x + 2x + 12 which equals 4x+12. When you subtract twelve from 100 you get 88=4x. Divide 88 by 4 and you get x=22. This then would mean the width is 22 and the length is 34. The formula for an area of a rectangle is w*l. Plug in the numbers that you figure out from the area formula and you get 22x34=748
Square b area = 144 ÷ 2
area = 72 in squared
area in feet = 6 ft squared
the answer is 10.6875 you divide 4. 75 and the number 100 them multiply your answer by 225
glad to help any time