Answer:
0.3667 or 36.67%
Step-by-step explanation:
The probability of getting at least 1 defective hard disk among the 5 (P(X>0)) is equal to 100% minus the probability of getting none defectives (1-P(X=0)).
If 23 out of 25 hard disks are non-defective, the probability is:

The probability that there is at least 1 defective hard disk is 0.3667 or 36.67%.
Answer:
2x²-32 ⇒ x²=16⇒ (-4,4)
4x²-100 ⇒x²=25 ⇒(-5,5)
x²-55=9 ⇒x²=64 ⇒(-8,8)
x²-140=-19 ⇒x²=121 ⇒(-11,11)
2x²-18=0 ⇒x²=9 ⇒(-3,3)
80/100*n=16
80n=1600
n=1600/80=160/8=20
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Original price: $20.00
Answer:
∠AEC = 139°
Step-by-step explanation:
Since EC bisects ∠BED then ∠BEC = ∠CED = 4x + 1
∠AED = ∠AEB + ∠BEC + ∠CED = 180 ← straight angle
Substitute values into the equation
11x - 12 + 4x + 1 + 4x + 1 = 180, that is
19x - 10 = 180 ( add 10 to both sides )
19x = 190 ( divide both sides by 19 )
x = 10
Hence
∠AEC = ∠AEB + ∠BEC = 11x - 12 + 4x + 1 = 15x - 11, hence
∠AEC = (15 × 10) - 11 = 150 - 11 = 139°