Answer: 1 hour 20 minutes
<u>Step-by-step explanation:</u>
Let's figure out how long it would take 1 person to dig the hole and then divide that number by 9 (since they are sharing the workload).

Based on my calculation i know for sure F
would equal 10
P(picking one defective) = 3/10
P(picking a 2nd defective) = 2/9
P(1 and 2 defective) = 3/10 x 2/9 = 6/90 = 0.066
Second method using combination:
³C₂ / ¹⁰C₂ = 1/15 = 0.066
take square root and subtract y2 from y1 and x2 from x1
Answer:
Step-by-step explanation:
To prove the triangle angle sum theorem,
We will do a construction by drawing a line PQ passing through point F and parallel to line DE.
Statements Reasons
1). ∠PFD + ∠QFD = 180° 1). linear pair postulate
2). ∠QFD = ∠QFE + ∠EFD 2). Angle addition postulate
3). ∠PFD + ∠QFE + ∠EFD = 180° 3). Substitution property
4). ∠PFD ≅ ∠FDE 4). Alternate interior angles
∠QFE ≅ ∠DEF
5). ∠FDE + ∠DEF + ∠EFD = 180° 5). Substitution property
Hence sum of interior angles of ΔDEF is 180°.