Correct Answers: | |
Wrong Answers: | |
Unattempted: |
Question 1
When a two digit number is reversed and added to itself we get 110. The product of the digits of that number is 21. What is the number?
73.
74.
72.
75.
Ans: a
Let the number be ab. When it is reversed and added to itself we get (10a + b) + (10b + a) = 11 × (a + b). We are given 110 = 11 × (a + b) ⇒ $a + b = 110 / 11 = 10$, so the digits are $a$ and $10 - a$. We are given their product as a × (10 - a) = 21, which is a quadratic expression that can be simplified to $(a - 7) × (3 - a) = 0$. So the number could be 73 or 37.
Question 2
The sum of two numbers is 25. Their difference is 19. They are in the ratio?
$7{1/3}$.
$12{1/2}$.
$6{1/3}$.
$6{1/5}$.
Ans: a
Let the numbers be a and b, and let their ratio be k such that $a/b = k$. We are given $a + b = 25$ ⇒ $b(k + 1) = 25$. Similarly, from the difference we can obtain $b(k - 1) = 19$. Dividing we get ${k + 1}/{k - 1} = 25/19$. By componendo and dividendo, $k = {25 + 19}/{25 - 19}$ = ${22/3}$, which is same as: $7{1/3}$.
Question 3
If ${23/34}$ of a number is 17, what is ${19/21}$ of that number?
Question 4
The sum of two numbers is 24. Their product is 143. One of the two numbers is?
Question 5
The sum of three consecutive integer numbers is -1113. The smallest of the three is?
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Problems on Numbers | abba Series | Passwords and Inputs | Problems on Ages | Boats and Streams | Square and Cube Roots | Ranking Test | Simple Interest | Surds and Indices | Venn Diagrams | More...
This Blog Post/Article "Problems on Numbers Quiz Set 009" by Parveen (Hoven) is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Updated on 2020-02-07. Published on: 2016-05-13