240 ARITHMETIC, 



23. A man dying left his wife in expectation, that a 

 child would be afterward added to the surviving family 5 

 and making his will ordered, that, if the child were a son, 

 y of his estate should belong to him, and the remainder to 

 his mother j but if it were a daughter, he appointed the 

 mother y, and the child the remainder. But it happened, 

 that the addition was both a son and a daughter, by which 

 the widow lest in equity 2400I. more than if there had been 

 only a girl : what would have been her dowry, had she 

 had only a son ? Ans. 2100I. 



24. A young hare starts 40 5''ards before a grey-hound, 

 and is not perceived by him till she has been up 40 sec- 

 onds j she scuds away at the rate of 10 miles an hour, 

 and the dog, on view, makes after her at the rate of 1 8* 

 How long witl the course continue, and what will be the 

 length of it from the place, where the dog set out ? 



Ans. 6o^~ seconds, and 530 yards rurl. 



25. A reservoir for water has two cocks to supply it ; 

 by the first alone it may be filled in 40 minutes, by the 

 second in 50 minutes, and it has a discharging cock, by 

 which it may, when full, be emptied in 25 minutes. Now,- 

 supposing that these three cocks are all left open, that the 

 water comes in, and that the influx and efflux of the wa- 

 ter are always alike, in what time would the cistern be 

 filled ? Ans. 3 hours 20 min. 



26. A sets out from London for Lincoln at the very 

 ^ame time that B at Lincoln sets forward for London, dis- 

 tant lOQ miles : after 7 hours they met on the road, and 

 it then appeared, that A had ridden i~ mile an hour more 

 than B : at what rate an hour did each of them travel ? 



Ans. A 7-|-|-, B 6~~ miles. 



27. What part of 3d. is. a third part of 2d. .? 



Ans. ^. 



28. A has by him i~cwt. of tea, the prime cost of 

 which was 96L sterling. Now, granting interest to be at 

 5 per cent, it is required to find how he must rate it per 



pound 



