Re: Due to a malfunctioning Heisenberg compensator in the transporter, Adr
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10 Sep 2022, 04:36
Due to a malfunctioning Heisenberg compensator in the transporter, Adriella was stranded in an Ardanian mine shaft. At 12:00, she uses her Type 1 phaser to cut through the zenite ore to open air, which will take 7 hours. At 12:30, Desmina, situated directly on the other side of the mineshaft, uses her Type 2 phaser to cut through the ore directly towards Adriella. If Desmina’s Type 2 phaser would have taken 6 hours to reach Adriella’s original location, what time did the two of them meet?
(A) 1:30
(B) 3:00
(C) 3:30
(D) 4:30
(E) 5:00
This is a relative speed problem which could be solved quicker with the application of ratios and how they inter relate with Rate & Time
Adri starts at 12 pm - It takes her 7 hrs to go the other side T = 7
Des starts at 12:30 - It takes her 6 Hrs to go the other side T = 6
Ratio of time of Adri : Desmi = 7 : 6
Ratio of rate of Desmi : Adri = 6 : 7
(In case of 2 bodies Ratio of Rate is inverse of ratio of time)
Lets say distance = 42 (LCM of 6 & 7)
Rate of Adri = 6mi/hr
Rate of Desmi = 7mi/hr
Combined Rate = 13 ( travelling in opposite directions)
Distance travelled by Adri in 30 mins . She starts 30 mins before Desmi = 6/2 = 3 Miles
Total Distance = 42 - 3 = 39 Miles
Time = 39/13 = 3 hrs . Time they both meet is 12:30 + 3hrs = 3:30 pm
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