After the 1st hour, Maxwell has travelled 4 Km. And Brad just left home. So the distance between them = 54 - 4 = 50.
Relative speed = 4 +6 = 10 Kmph.
Now to cover these 50 Kms, they will take 50/10 = 5 Hrs. So in 5 hrs, Maxwell walks 5*4 = 20 Kms.
So total distance travelled by Maxwell = 4 + 20 = 24. Hence D.

d = 54 km
rM = 4 km/h
rB = 6 km/h

We know that if two people started walking towards at the same time, the time travelled at the time of meeting each other is the same. In this case, Maxwell leaves 1 hour earlier. Then, if
tM = x, then
tB = x -1

We know that at the time M & B meet, they would have together travelled the total distance:
Total distance = tM * rM + tB * rB = 54
x * 4 + (x-1) * 6 = 54
4x + 6x - 6 = 54
10x = 60
x = 10

Total Distance = 54 kms
Maxwell Speed = 4 kms/hr
Maxwell traveled for 1hour before Brad started , therefore Maxwell traveled for 4 kms in 1 hour.

Time taken = Total Distance / Relative Speed
Total Distance after Brad started = 50 kms
Relative Speed (Opposite side) (As they are moving towards each other speed would be added ) = 6+ 4 = 10 kms/hr

Time taken = 50 / 10 = 5 hrs
Distance traveled by Maxwell = Maxwell's speed * time taken = 4 * 5 = 20+4 = 24 kms... Answer - D

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I understand question as: the diatance travelled by Maxwell when both of them meet.

In the first hour Maxwell walks: (4km/h) * 1 hr = 4 Km

Now the distance between Maxwell and Brad is 54-4 = 50 Km
Both are moving towards each other.

Relative Speed = 6+ 4 = 10 Km/h

They will cross each other at (50/10) hours = 5 hours.

Maxwell walked for these 5 hours = 5 * 4 = 20 Km.

Total distance = 20+ 4 = 24 Km

D is the option.

Brad Started his travel I hour later,so their distance remains after 1 hour =(54-4)=50

they run 50 km with their individual to meet each other.

So,Each answer choice subtracted by 4 ,indicates Maxwell's traveled distance of 50 km and the rest of the distance traveled must be matched with Brad's traveled distance.

Only Answer Choice D matched this criteria. Maxwell's total travel distance =24,Contribution towards travelling distance of Maxwell=24-4=20,Remained 30km (50-20) is Brad'd traveled distance ,since it is only divisible by Brad's speed(6km/h)


Correct answer D

I believe that the question should mention- 'what is the distance travelled by Maxwell when they both met'

Maxwell travelled 4 Kms for 1 hr while brad was not moving.

Remaining distance= 50
Relative speed= 4+6= 10

Time travelled to meet each other= 50/10= 5hrs

Maxwell travelled total for 5 hrs or 20 kms + 4 kms = 24 kms

D is the answer
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(54-4)/(4+6)=5 hrs
5*4+4=24 miles for M

I think the question must be re-worded: what distance did Maxwell walk by the time he met with...

Yeah the question should be reworded. It should specify the point in time for which we are measuring. Maxwell can possibly keep walking for all of the 54 km. The question doesn't specify where to stop so technically he could walk any measure of the distance between 4-54.

We can let Brad’s time = t, and thus Maxwell’s time = t + 1. Furthermore, since distance = rate x time, Brad’s distance = 6t and Maxwell’s distance = 4(t + 1). Since their total distance is 54 km, we can create the following equation:

Brad’s distance + Maxwell’s distance = 54

6t + 4(t + 1) = 54

6t + 4t + 4 = 54

10t = 50

t = 5

Thus, Maxwell has traveled 4(5 + 1) = 24 km when they meet.

Answer: D
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