Let D be Daniel's present age, then we can represent Kevin's present age as 3D because Kevin is 3 times as old as Daniel.
We can write an expression for Daniel's age 4 years ago as D-4 and Kevin's age 4 years ago as 3D-4.
We are told that 4 years ago Kevin was 5 times as old as Daniel. We can write this information as:
Now let us solve our equation to find Daniel's present age.
Daniel's present age is 8 years. Now we will multiply 8 by 3 to get Kevin's present age as Kevin is 3 times old as Daniel.
Therefore, Kevin is 24 years old now.
Answer:
Diameter = 23 Radius = 11.5
Step-by-step explanation:
Divide the circumference by π, or 3.14 for an estimation. The result is the circle's diameter.
<em>72.22 ÷ 3.24 = 23</em>
diameter = 23
Divide the diameter by 2.
<em>23 ÷ 2 = 11.5</em>
There you go, you found the circle's radius
Answer:
Step-by-step explanation:
There is a 1/12 probability that volume 1 will be correctly put in position 1.
If we assume that volume 1 is right, then since there are then only 11 books left to choose from, there is then a 1/11 prob that volume 2 will be in position 2. And so on. By the same reasoning there is 1/10 prob that volume 3 is then right, 1/9 prob for volume 4, 1/8 prob for volume 5, and 1/7 prob for volume 6,
and 1/6 prob for volume 7,and 1/5 prob for volume 8,and 1/4 prob for volume 9,and 1/3 prob for volume 10,and 1/2 prob for volume 11,and 1/1 prob for volume 12.
So the probability is 1 /(12*11*10*9*8*7*6*5*4*3*2*1) = 1 / 479,001,600 ....
