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ഒരു കാർ യാത്രയുടെ ആദ്യ 1/2 ഭാഗം 10 km/hr വേഗതയിലും അടുത്ത 1/2 ഭാഗം 30 km/hr വേഗതയിലും സഞ്ചരിക്കുന്നു . യാത്രയുടെ ശരാശരി വേഗത എത്രയാണ് ?

A30 km/hr

B45 km/hr

C40 km/hr

D15 km/hr

Answer:

D. 15 km/hr

Read Explanation:

അകെ ദൂരം 2X ആണെങ്കിൽ

X ദൂരം സഞ്ചരിച്ച വേഗത - 10 km/hr

സമയം= X/10

തിരിച്ചുള്ള X ദൂരം സഞ്ചരിച്ച വേഗത - 30 km/hr

സമയം = X/30

ആകെ സമയം = X/10 + X/30

=2X/15

ആകെ ദൂരം = 2X

ശരാശരി വേഗത = 2X/(2X/15)

=15 km/hr

 

OR

X = 10, Y = 30

ശരാശരി വേഗത= 2xy/(x+y)

 

= 2 × 10 × 30/(10+30)

 

= 600/40

 

= 15km/hr


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