Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
216 views
in Aptitude by (115k points)
closed by
X, Y and Z travel from the same place with uniform speeds 4 km/hr, 5 km/hr and 6 km/hr respectively. Y starts 2 hours after X. How long after Y must Z start in order that they overtake X at the same instant?
1. \(\frac{3}{2} hours\)
2. \(\frac{4}{3} hours\)
3. \(\frac{9}{8} hours\)
4. \(\frac{11}{8} hours\)

1 Answer

0 votes
by (114k points)
selected by
 
Best answer
Correct Answer - Option 2 : \(\frac{4}{3} hours\)

Given:

Speed of X, Y and Z = 4 km/h, 5 km/h and 6 km/h.

Formula used:

Distance = Speed × Time

The relative speed of Y with respect to X = (Sx - Sy)

Where Sx and Sy are the speed of X and Y respectively.

Calculation:

Distance covered by X in 2 hours = 4 × 2

⇒ Distance covered by X in 2 hours = 8 km

Time required for Y to cover this distance = 8/(5 - 4)

⇒ Time required for Y to cover this distance = 8 hours

Let Z starts t hours after Y.

According to the question,

8 × 5 = (8 - t) × 6

⇒ 40 = 48 - 6t

⇒ 6t = 8

⇒ t = 4/3 

∴ Z starts travelling 4/3 hours after Y.

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...