Ali's solution is incorrect
same as 9y + 1y
10y
<span>As the age of the U-235 sample is 2.631 billion years, and the half-life of U-235 is 713 million years, the sample has undergone 2.361 X 1,000,000,000 / 713 X 1,000,000 = 3.69 half lives. In each half-life the sample reduces to half its original weight according to the radioactive Half-Life Formula:
ln (Nt /N0) = -kt, where N0 = mass of the original weight of radioactive material, Nt = mass of radioactive material at time t, k = decay constant and t = time interval . We have to put Nt/N0 = 1/2 for time interval = half-life.</span>
Answer:
Area of the square is 2916
.
Step-by-step explanation:
Let the breadth of the rectangle be represented by w. So that;
length of rectangle = 5w
Area of rectangle = length x breadth
= 5w x w
1620 = 5
divide through by 5 to have,
= 324
w = 
= 18
Thus, the breadth of the rectangle is 18 m.
length = 5 w = 5 x 18
= 90 m
The length of the rectangle is 90 m.
Perimeter of the rectangle = 2(l + w)
= 2( 90 + 18)
= 216 m
Perimeter of a square = 4l
where l is the length of its side.
Given that the perimeters of the rectangle and square are equal, then;
4l = 216
l = 
= 54
length of the side of square is 54 m.
Therefore,
Area of square = 
= 
= 2916
Area of the square whose perimeter is equal to that of the rectangle is 2916
.