A shopkeeper buys a number of books for Rs. 80. If he had bought

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsLong Answer Type

191. The altitude of a right triangle is 7 cm less than its base. If the hypotenuse is 13 cm. Find the other two sides.
128 Views

192. The sum of the areas two squares is 640 m2. If the difference in their perimeter be 64 m, Find the sides of the two squares.
517 Views

193. If twice the area of a smaller square is subtracted from the area of a larger square, the result is 14 sq cm. However, if twice the area of larger square is added to three times the area of the smaller square, the result is 203 sq. cm. Find the sides of the two squares.
133 Views

 Multiple Choice QuestionsShort Answer Type

194. The hypotenuse of a right triangle is 3 square root of 5 space cm. If the smaller side is tripled and the larger side is doubled, the new hypotenuse will be 15 cm. Find the length of each side.
278 Views

Advertisement

 Multiple Choice QuestionsLong Answer Type

195. A farmer wishes to grow a 100 mrectangular vegetable garden. Since he has with the only 30 m barbed wire, he fences three sides of the rectangular garden letting compound wall of his house act as the four the side-fence. Find the dimension of his garden.
164 Views

196. There is a square field whose side is 44 m. A square flower bed is prepared in its centre leaving a gravel path all round the flower bed. The total cost of laying the flower bed and gravelling the path at Rs. 2.75 and Rs. 1.50 per square metre, respectively, is Rs. 4904. Find the width of the gravel path.
1588 Views

197. Two pipes running together can fill a cistern in space space 3 1 over 13 space minutes. If one pipe takes 3 minutes more than the other to fill it, find the time in which each pipe would fill the cistern.
153 Views

198. A person on tour has Rs. 360 for his expenses. If he extends his tour for 4 days, he has to cut down his daily expenses by Rs. 3. Find the original duration of the tour.
406 Views

Advertisement
199. Rs. 6500 were divided equally among a certain number of persons. Had there been 15 more persons, each would have got Rs. 30 less. Find the original number of persons.
454 Views

Advertisement

200. A shopkeeper buys a number of books for Rs. 80. If he had bought 4 more books for the same amount, each book would have cost Rs. 1 less. How many books did he buy?


Let the number of books bought be x. Then,
Cost of x books = Rs. 80
rightwards double arrow         Cost of one book = Rs. open parentheses 80 over straight x close parentheses
If the number of books bought is x + 4, then
Cost of one book  = Rs. space open parentheses fraction numerator 80 over denominator straight x plus 4 end fraction close parentheses
According to given condition,

∴                  80 over straight x minus fraction numerator 80 over denominator straight x plus 4 end fraction equals 1

rightwards double arrow            space space 80 open parentheses 1 over straight x minus fraction numerator 1 over denominator straight x plus 4 end fraction close parentheses space equals space 1

rightwards double arrow space space space space space space space space space space 80 open curly brackets fraction numerator straight x plus 4 minus straight x over denominator straight x left parenthesis straight x plus 4 right parenthesis end fraction close curly brackets equals 1

rightwards double arrow                          fraction numerator 320 over denominator straight x squared plus 4 straight x end fraction equals 1
rightwards double arrow                       straight x squared plus 4 straight x equals 320
rightwards double arrow             straight x squared plus 4 straight x minus 320 space equals space 0
rightwards double arrow space space space straight x squared plus 20 straight x minus 16 straight x minus 320 space equals space 0
rightwards double arrow     straight x left parenthesis straight x plus 20 right parenthesis minus 16 left parenthesis straight x plus 20 right parenthesis space equals 0
rightwards double arrow space space space space space space space space space space space space space space space space space space space space left parenthesis straight x plus 20 right parenthesis space left parenthesis straight x minus 16 right parenthesis space equals space 0
rightwards double arrow                                space straight x equals negative 20
or                                   straight x equals 16
rightwards double arrow                                  straight x equals 16
[∵ x cannot be negative]
Hence, the number of books is 16.

 
664 Views

Advertisement
Advertisement