Advertisements
Advertisements
Question
Set up equation and solve them to find the unknown number in the following case:
If I take three-fourths of a number and add 3 to it, I get 21.
Solution
Let the number be x
Three-fourth of this number = `(3x)/4`
`3/4x + 3 = 21`
`3/4x` = 18 ...(Transposing 3 to R.H.S)
Multiplying both sides by 4
`(3x xx 4)/4`
= 18 × 4
3x = 72
Dividing both sides by 3,
`(3x)/3 = 72/3`
x = 24
APPEARS IN
RELATED QUESTIONS
Laxmi’s father is 49 years old. He is 4 years older than three times Laxmi’s age. What is Laxmi’s age?
Sum of two numbers is 81. One is twice the other.
The equation formed is ______.
In a Mathematics quiz, 30 prizes consisting of 1st and 2nd prizes only are to be given. 1st and 2nd prizes are worth ₹ 2000 and ₹ 1000, respectively. If the total prize money is ₹ 52,000 then show that:
The equation formed is ______.
The interest received by Karim is ₹ 30 more than that of Ramesh. If the total interest received by them is ₹ 70, find the interest received by Ramesh.
Two times a number increased by 5 equals 9. Find the number.
After 20 years, Manoj will be 5 times as old as he is now. Find his present age.
In a bag, the number of one rupee coins is three times the number of two rupees coins. If the worth of the coins is ₹ 120, find the number of 1 rupee coins.
The perimeter of a rectangle is 40 m. The length of the rectangle is 4 m less than 5 times its breadth. Find the length of the rectangle.
The sum of two consecutive multiples of 2 is 18. Find the numbers.
What does a duck do when it flies upside down? The answer to this riddle is hidden in the equation given below:
If i + 69 = 70, then i = ? If 8u = 6u + 8, then u = ?
If 4a = –5a + 45, then a = ? if 4q + 5 = 17, then q = ?
If –5t – 60 = – 70, then t = ? If `1/4`s + 98 = 100, then s = ?
If `5/3`p + 9 = 24, then p = ______?
If 3c = c + 12, then c = ______?
If 3 (k + 1) = 24, then k = ______?
For riddle answer: substitute the number for the letter it equals
`()/1 ()/2 / ()/3 ()/4 ()/5 ()/6 ()/7 ()/8/()/4 ()/9`
