Answer: d. The helicopter rotor will spin 36,000 times in 1 hour
Step-by-step explanation:
Option A is wrong because in 40 minutes the rotor will spin:
= 40 * 600
= 24,000 times
Option B is wrong because we cannot know the number of times the rotor will spin before being lifted off of the ground with the details given.
Option C is wrong because in 3 hours the rotor will spin:
= 600 * 3 * 60 minutes
= 108,000 times
Option D is correct because in 1 hour the rotor will spin:
= 600 * 1 * 60 mins
= 36,000 times
3(d + 11) = 6(d + 33)
So you have: 3d + 33 = 6d + 198
which is: -3d = 165
or d = -55
So you have <em>only one answer.</em>
Answer:
i hope this helps
Step-by-step explanation: