Advertisements
Advertisements
प्रश्न
In a two digit number, the unit’s digit is twice the ten’s digit. If 27 is added to the number, the digit interchange their places. Find the number.
Advertisements
उत्तर
Let ten's digit = x
Unit's digit = 2x
Required number
= 10x + 2x
= 12x
On interchanging the digit's
Number formed
= 10 (2x) + x
= 21x
According given condition
12x + 27 = 21x
27 = 21x - 12x
27 = 9x
∴ x = `(27)/(9)`
x = 3
∴ Required number
= 12 x 3
= 36.
संबंधित प्रश्न
Solve for x :
`3/(x+1)+4/(x-1)=29/(4x-1);x!=1,-1,1/4`
Solve the following quadratic equations by factorization:
`(x+1)/(x-1)-(x-1)/(x+1)=5/6` , x ≠ 1, x ≠ -1
A two digit number is such that the product of the digits is 16. When 54 is subtracted from the number the digits are interchanged. Find the number
An aeroplane left 50 minutes later than its scheduled time, and in order to reach the destination, 1250 km away, in time, it had to increase its speed by 250 km/hr from its usual speed. Find its usual speed.
Solve the following quadratic equations by factorization:
`(3x-2)/(2x-3)=(3x-8)/(x+4)`
The positive value of k for which the equation x2 + kx + 64 = 0 and x2 – 8x + k = 0 will both have real roots, is ______.
If sin α and cos α are the roots of the equations ax2 + bx + c = 0, then b2 =
Solve the equation 2x `-(1)/x` = 7. Write your answer correct to two decimal places.
A shopkeeper buys a certain number of books for Rs 960. If the cost per book was Rs 8 less, the number of books that could be bought for Rs 960 would be 4 more. Taking the original cost of each book to be Rs x, write an equation in x and solve it to find the original cost of each book.
A man spent Rs. 2800 on buying a number of plants priced at Rs x each. Because of the number involved, the supplier reduced the price of each plant by Rupee 1.The man finally paid Rs. 2730 and received 10 more plants. Find x.
