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It takes eight hours for a 600 km journey, if 120 km is done by train  and the rest by car. It takes 20 minutes more, if 200 km is done by  train and the rest by car. The ratio of the speed of the train to that  of the cars is:

A.  2 : 3 B. 3 : 2  C. 3 : 4   D. 4 : 3

shortest approach other than options and forming eqn

What angle will the hour hand and minute hand make at 2:30 am ?

shortest way to solve this

A boat goes 2km upstream and 3km downstream in 20minutes. It goes 7km upstream and 2km downstream in 53 minutes,What is the speed of boat(km/hr) in still water?

shortest possible method

The difference between compound interest and simple interest on a certain sum of money at 12.5% per annum for 2.5 year is 495.Find the principal

# A shopkeeper buys two cameras at the same price. he sells one camera at a profit of 18% and the other at a price 10% less than the selling price of the first. Find his profit or loss pecentage

The monthly income of Aand B are in ratio 9:7 and expenditure 4:3 resp. If each saves rs 1600 ,then find monthly income of each

what is the hcf of( x^4-x^2-6) and (x^4-4x^2+3)?

options

x^2-3

x^2+3

x+2

x+3

Three labourers, working together can dig a pit 324 m deep in 6 days. In one shift, third labour digs as many extra metres from second labour as second labour digs extra from first labour. Work done by the third labour in 10 days is equivalent to the work done by first labour in 14 days. How many metres does the first labour dig in one shift?

A person had Rs. 6800. He invested a part of his money at 10% simple interest and the remaining on 7.5% simple interest. Find the money invested at 10% p.a. if he gets Rs. 1904 as an interest after 3 1/2  years.

A book - seller bought 200 te x tbooks for Rs. 12 , 000. He wanted to sell them so that he got profit equal to cost price of 20 books. At what profit percent should he sell them?

SI & CI difference for 2 years at rate of 20% is 200. What wil be t CI if calculated half yearly