20 Questions

Questions and Answers

- 1.Note: Input fraction for 1.5 as 1+1/2Input fraction for 2.3 as 2+1/3
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- 4.Give your answers in fraction.Note: Input 1.5 as 1+1/2 INput 2.333... as 2+1/3
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- 6.A certain number has exactly eight factors, of which 35 and 77 are two. Find the number.
- 7.Find the smallest positive integer which has amongst its factors 2,3,10,15,20,21,and 28.
- 8.Find the smallest five-digit number that contains all different even digits and has 16 as one of its factors.
- 9.A three digit number has the property that if you subtract 7 from it the result is divisible by 7, if you subtract 8 from it the result is divisible by 8 and if you subtract 9 from it the result is divisible by 9. What is the number?
- 10.A seminar is attended by 96 students from iSpark, 72 students from Aphelion and 48 students from ProEd. What is the greatest number of groups that can be formed so that the students from each consortium are distributed equally among all the groups?
- 11.Prime Factorise 2205 x 4200.Then find the cube root of 2205 x 4200 without using a calculator.
- 12.Find the HCF of 450, 2655 and 180.
- 13.Find the LCM of 40, 24 and 36.
- 14.Given that sqrt(720) =26.8 and sqrt(72) = 8.5, find the value of sqrt(0.72) without using calculator.Note: sqrt means square root
- 15.Express 100.75376 to 3 significant figures. Note: Give your answer only. Not need to add (3 sig fig)
- 16.Express 4.9902 to 2 significant figures. Note: Give your answer only. Not need to add (2 sig fig)
- 17.Express 0.0003804 to 3 significant figures. Note: Give your answer only. Not need to add (3 sig fig)
- 18.Express 3.0563 x 10
^{3}to 3 significant figures. Note: Give your answer only. Not need to add (3 sig fig)Input standard form as ___ x 10^__. For example : 1.2 x 10^3 - 19.Express 12906310 to 3 significant figures. Note: Give your answer only. Not need to add (3 sig fig)
- 20.Find the LCM of the numbers 1 to 20.