Advertisements
Advertisements
Question
In a two-digit number, digit in units place is twice the digit in tens place. If 27 is added to it, digits are reversed. Find the number.
Solution
Let ten’s digit of two-digit number be x.
Then unit’s digit = 2x
∴ Number = 10 × x + 2x
= 10x + 2x
= 12x
On reversing the digits,
New number = 10 × (2x) + x
= 20x + x
= 21x
12x + 27 = 21x
⇒ 21x – 12x = 27
⇒ 9x = 27
⇒ x = 3
Hence, the required number is 12 × 3, i.e. 36.
APPEARS IN
RELATED QUESTIONS
Amina thinks of a number and subtracts `5/2` from it. She multiplies the result by 8. The result now obtained is 3 times the same number she thought of. What is the number?
One of the two digits of a two digit number is three times the other digit. If you interchange the digit of this two-digit number and add the resulting number to the original number, you get 88. What is the original number?
There is a narrow rectangular plot, reserved for a school, in Mahuli village. The length and breadth of the plot are in the ratio 11:4. At the rate Rs 100 per metre it will cost the village panchayat Rs 75, 000 to fence the plot. What are the dimensions of the plot?
Hasan buys two kinds of cloth materials for school uniforms, shirt material that costs him Rs 50 per metre and trouser material that costs him Rs 90 per metre. For every 2 meters of the trouser material he buys 3 metres of the shirt material. He sells the materials at 12% and 10% profit respectively. His total sale is Rs 36660. How much trouser material did he buy?
Half of a herd of deer are grazing in the field and three fourths of the remaining are playing nearby. The rest 9 are drinking water from the pond. Find the number of deer in the herd.
A grandfather is ten times older than his granddaughter. He is also 54 years older than her. Find their present ages
Aman’s age is three times his son’s age. Ten years ago he was five times his son’s age. Find their present ages.
In a 2 digit number, the units place digit is x. If the sum of digits be 9, then the number is (10x – 9).
Sum of the digits of a two-digit number is 11. The given number is less than the number obtained by interchanging the digits by 9. Find the number.
After 12 years, Kanwar shall be 3 times as old as he was 4 years ago. Find his present age.
