A can complete a piece of work in 4 days. B takes double the time taken by A, C takes double that of B, and D takes double that of C to complete the same task. They are paired in groups of two each. One pair takes two-thirds the time needed by the se ?->(Show Answer!)

1. A can complete a piece of work in 4 days. B takes double the time taken by A, C takes double that of B, and D takes double that of C to complete the same task. They are paired in groups of two each. One pair takes two-thirds the time needed by the second pair to complete the work. Which is the first pair?

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By: anil on 05 May 2019 02.31 am

A takes 4 days to complete the work.
So, B takes 8 days to complete the same work.
C takes 16 days to complete the work.
D takes 32 days to complete the same work.

In order to measure, let the total work be of 64 units. Hence, the speed of working of each of the four persons is given below.

A - 16 units/hr
B - 8 units/hr
C - 4 units/hr
D - 2 units/hr

From the given options, we need to find two pairs in such a way that their speeds are in the ratio 3:2. Note that A+D=18 while B+C=12 and the ratio is 3:2 Hence, the first pair is A and D and the second pair is B and C

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MCQ-> Read the following passage carefully and answer the questions given below it. Certain word/phrases have been printed in bold to help you locate them while answering some of the questions.The men of Suvarnanagari were very lazy. They only liked to gossip and tell each other tall tales. As soon as the sun rose, the men would tuck into hearty breakfast and then gather in groups for their daily session of gossiping. Then they would spend the rest of the day telling each other impossible stories. They came back only at lunch and dinner time. The farmlands of Suvarnanagari were very fertile. If the men had spent even a little time at fields, they would have reaped wonderful crops. But as they did nothing, all the responsibilities ended up on shoulders of the woman. They had to work hard the whole day. They cooked, cleaned, sent the children to school, worked in the fields, took the crops to the market - in short they did everything. One day the tired woman gathered and decided that the men needed to be taught a lesson. One of them suggested that they should write to the king about their problem, as he was known to be just and a kind person. So the letter was written and sent to the king. The women went back to their daily routines, hoping that the king would soon take some action. Many days passed, nothing changed, no one came, and the poor women began to lose hope. ‘After all why would the king of such a vast empire be concerned about the plight of the women of such a tiny village?’ they thought. A month passed by and it was a full moon night. The men ate their dinners and because it was so beautiful and well lit outside, they gathered again to chat and boast. That night they were trying to prove to one another that they were capable of performing the most impossible tasks. Soon a tall and handsome stranger joined them. Seeing his noble features and intelligent eyes, each one wanted to prove himself better than the others and impress to him. One said, ‘’I knew the map of this kingdom even before I was born. I ran to meet the king as soon as I was born, my mother had such trouble bringing me back home !’’ Everyone was impressed by this story. Soon another man said, ‘’So what is so great about that ? When I was a just a day old, I could ride a horse. I sat on a big horse and rode all the way to the king’s palace. He received me with lot of love and we had the most delicious meal together.’’ This was even more impressive, so everyone applauded. Now the third man said, ‘’Huh! That is nothing. I sat on an elephant when I was a week old and had lunch with the king in his palace.’’Before the admiring murmurs could die down, the fourth man said, ‘’When I was a month old, I flew like a bird and landed in the king’s garden. The king picked me up and even let me sit on his throne with him,’’ While everyone was in awe of these stories, the stranger spoke up, ‘’ Do all four of you know the king very well?’’ ‘’Of course we do! ‘’ they replied together. ‘’Our king knows and love us. In fact, he is proud to have supernatural beings like us in his kingdom,’’ one of them added. The stranger looked thoughtful. ‘’That makes my task so much easier. You see, I work in the king’s court. Some days ago the king had summoned four supermen to the city in order to repair a large hole in the city wall. As you know, we use only the largest and toughest stones for building these walls, and they could be lifted and put in place only by these supermen. The four supermen asked to be paid in gold bars and the king complied.But the night they received their fee, they disappeared from the palace. I have been wandering around ever since looking for them. The king has ordered me to find the four men and bring them back to the capital to finish the work. They will also have to return the gold bars they ran away with. It looks like the search has finally ended. I will take the four of you to the king along with the gold bars. The king will be very pleased with me and will surely reward me,’’ said the stranger. By the time the stranger finished his story, the four men realised that their lies had landed them into a huge trouble. Their faces turned ashamed and they dived at the stranger’s feet. ‘’Those were all lies. We are all just a bunch of lazy men. But if you forgive us and forget our stories, we promise to do some honest work and stop telling such lies,’’ they wailed. The stranger smiled and said, ’’Alright, I will tell the king there are no supermen in this village, just honest and hardworking men and women.’’ That night the stranger left the village. The women were sure that it was none other than the king himself.How did the men of Suvarnanagiri spend their days ?
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MCQ-> In a modern computer, electronic and magnetic storage technologies play complementary roles. Electronic memory chips are fast but volatile (their contents are lost when the computer is unplugged). Magnetic tapes and hard disks are slower, but have the advantage that they are non-volatile, so that they can be used to store software and documents even when the power is off.In laboratories around the world, however, researchers are hoping to achieve the best of both worlds. They are trying to build magnetic memory chips that could be used in place of today’s electronics. These magnetic memories would be nonvolatile; but they would also he faster, would consume less power, and would be able to stand up to hazardous environments more easily. 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