Question
A two-digit number has a sum of its digits equal to 8.
Additionally, if 27 is subtracted from this number, the resulting number has its digits reversed. What is the original number?Solution
ATQ,
Let ones and tens digit of the number be 'a' and 'b' respectively.
So, original number = 10b + a
Reverse number = 10a + b
So,
a + b = 8 --------- (I)
And, 10b + a - 27 = 10a + b
Or, 9b - 9a = 27
Or, b - a = 3 ---------- (II)
On adding equation I and II,
We get, a + b + b - a = 8 + 3
Or, 2b = 11
Or, 'b' = 5
On putting value of 'b' in equation I,
We get, 5 + a = 8
Or, 'a' = 3
Required number = 10 × 5 + 3 = 53
Ajay spent 34% of his monthly income on rent and 48% of the remaining on food and the rest amount is saved by him which is Rs. 2574, then find the month...
Monthly income of Aisha and Tom is Rs. 75,200 and Rs. 82,000 respectively. Aisha spends 13%, 18%, and 22% on house rent, food, and education of children...
Suresh spends 30% of his monthly salary on travel, 40% of the leftover on food, and saves the remaining amount. If he saves Rs. 1680, find out how much ...
A student multiplied a number by 8/5 instead of 5/8. What is the percentage error in the calculation?
- Neha spent 30% of her income on education and out of the remaining amount, she spent 25% on travel, 20% on health, 15% on entertainment, and saved Rs. 2000...
Tim spends 22% of his monthly income in travelling. He spends 25% of his monthly income on household expenses and spends 36% of his monthly income on fa...
Ravi had Rs. 20,000. He donated 15% of the total for disaster relief, then gave 10% of the remaining for rural education, and 30% of what was left for o...
A TV was available for Rs 14,500. The price came down to Rs 11,890 during the Diwali sale. What is the percentage discount?
Ravi had 360 candies, while Shyam had 45 more candies than Ravi. Ravi ate 25% of his candies, and Shyam ate 35% of his candies. N...
In 2011, the total population of a village was 5280, Out of which 30% were female. In 2012, the total population increased by 10% in comparison to the p...