Question
What is the term used for the process of removing
calcium and magnesium from hardwater?ÂSolution
Water softening is the removal of calcium, magnesium, and certain other metal cations in hard water. The resulting soft water requires less soap for the same cleaning effort, as soap is not wasted mopping up calcium ions.
- Two numbers have a sum of 112. If their LCM is 420 and HCF is 6, determine the smaller number.
If a, 1, b are in arithmetic progression and 1, a, b are in geometric progression, then a and b are respectively equate to _______ (where a ≠b).
Raj scored 140 marks in a test getting 3 marks for each right answer and losing 1 mark for each wrong answer, had 4 marks been awarded for each correct...
Find the value of 6 + 66 + 666 + 6666 +hellip;hellip;hellip;hellip;.. + n terms.
1. `(2)/(3) ((10 xx (10^(n)- 1))/9 - n)`
2.
- Find the median of the following observations:
120, 125, 115, 130, 140, 135, 145 Find the greatest 3-digit number which is exactly divisible by 7, 8 and 9.
How many unique five-digit numbers can be created using the digits 0, 1, 5, 6, 7, and 8, without repeating any digit?
- When is the expression 16x - 4x² - 48 greater than zero?
A = (7/3) × B and C = (1/14) × A. If (A + B + C) = 360, then determine the value of (10C – B).
Nine numbers are arranged in decreasing order. The average of the first eight numbers is 50, and the average of the last eight numbers is 45. What is th...
