The number of permutations of picking 4 pens from the box is 30.
There are six different unique colored pens in a box.
We have to select four pens from the different unique colored pens.
We have to find in how many different orders the four pens can be selected.
<h3>What is a permutation?</h3>
A permutation is the number of different arrangements of a set of items in a particular definite order.
The formula used for permutation of n items for r selection is:

Where n! = n(n-1)(n-2)(n-3)..........1 and r! = r(r-1)(r-2)(r-3)........1
We have,
Number of colored pens = 6
n = 6.
Number of pens to be selected = 4
r = 4
Applying the permutation formula.
We get,
= 
= 6! / 4!
=(6x5x4x3x2x1 ) / ( 4x3x2x1)
= 6x5
=30
Thus the number of permutations of picking 4 pens from a total of 6 unique colored pens in the box is 30.
Learn more about permutation here:
brainly.com/question/14767366
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Answer:
BC = 22
Step-by-step explanation:
<b = <c given
we now know it is an isosceles triangle
therefore AC = AB
AC=AB
2x-24 = x-2
subtract x from each side
2x-x-24 = x-2-x
x-24 =-2
add 24 to each side
x-24+24 = -2+24
x = 22
side BC = x
BC = 22
OK. I did it. Now let's see if I can go through it without
getting too complicated.
I think the key to the whole thing is this fact:
A radius drawn perpendicular to a chord bisects the chord.
That tells us several things:
-- OM bisects AB.
'M' is the midpoint of AB.
AM is half of AB.
-- ON bisects AC.
'N' is the midpoint of AC.
AN is half of AC.
-- Since AC is half of AB,
AN is half of AM.
a = b/2
Now look at the right triangle inside the rectangle.
'r' is the hypotenuse, so
a² + b² = r²
But a = b/2, so (b/2)² + b² = r²
(b/2)² = b²/4 b²/4 + b² = r²
Multiply each side by 4: b² + 4b² = 4r²
- - - - - - - - - - -
0 + 5b² = 4r²
Repeat the
original equation: a² + b² = r²
Subtract the last
two equations: -a² + 4b² = 3r²
Add a² to each side: 4b² = a² + 3r² . <=== ! ! !