Need help solving 2 quant questions

Question

Hey. I am struggling with these two questions. What are the best way to solve them? Thanks!!!

question 1

First day of vacation, Joe traveled 216 miles. 2nd day of vacation, traveling at the same average speed, he traveled 378 miles. If the 216 mile trip took 3 hours less than 378 mile trip, what was avg speed in mph?
a)31
b)38
c)50
d)54
e)56

question 2

Pat bought N apples at cost of 3 for $0.20 and then sold the N apples at price of 4 for $0.35. If Pat's revenue from sale of the apples was $2.50 more than the cost of the apples, what is the value of n?

a)150
b)120
c)90
d)80
e)60

shrouded1 · Answer

Question 1

Extra miles covered = 378-216 = 162
Extra time taken = 3 hours
So speed = 162/3 = 54mph
Answer : d

Question 2

Profit per 12 apples sold = 3*0.35 - 4*0.20 = 0.25
Total profit = 2.5
So apples sold = 12 * (2.5/0.25) = 120
Answer : b

muralimba · Answer

1.
Distance=Speed * Time
216=ST
378=S(T+3)==> 378-3S=ST=216==>S=(378-216)/3 = 162/3=54 Answer: D

2.

Buying cost:
cost of 3 apples = 0.35
==> cost of 1 apple = 0.35/3
==> cost of n apples = n(0.35)/3

Selling cost:
cost of 4 apples = 0.20
==> cost of 1 apple = 0.20/4
==> cost of n apples = n(0.20)/4

qtn says profit = 2.5
==> buying cost - selling cost = 2.5
==> n(0.35)/3 - n(0.20)/4 = 2.5...solving for n will yeild n=120 ...answer:B

Hopw it helps.

jpr200012 · Answer

Question 1, I usually make a RTD chart:

R * T = D
Day 1 x y-3 216
Day 2 x y 378

Solve for x.

xy - 3x = 216  (1)
 xy = 378  (2)

We can plug (2) into (1) for xy:
 378 - 3x = 216

Now solve:

3x = 162

x = 54

jpr200012 · Answer

Question 2, another chart to start:

Action Count Rate Cost
Bought N  \frac{.2}{3}   x 
Sold N  \frac{.35}{4}   2.50 + x

Count * Rate = Cost

\frac{.2N}{3} = x  (1)
 \frac{.35N}{4} = x + 2.5  (2)

Now substitute (1) into (2).

\frac{.35N}{4} = \frac{.2N}{3} + 2.5

Now solve for N.

1 = \frac{4}{.35N} * (\frac{.2N}{3} + 2.5)

1 = \frac{16}{21} + \frac{200}{7N}

\frac{5}{21} = \frac{200}{7N}

35N = 4200

N = 120

jpr200012 · Answer

Sorry, the tabs in my tables didn't come out right on here. I hope the tables make sense.

rtaha2412 · Answer

Thanks for the help !

Posted from my mobile device

bumpbot · Answer

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Need help solving 2 quant questions

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