Question

A two-digit number is equal to 7 times the sum of its digits. The number formed by reversing its digits is 18 less than the original number. Find the original number.

Answer 1

Answer:

42

Step-by-step explanation:

Let no. be 10$x$+$y$

∴10$x$+$y$=7($x+y$)

⇒$10x+y=7x+7y$

⇒$3x=6y$

⇒$x=2y$   ............(1)

also, $10y+x=10x+y-18$

    ⇒$9y+18=9x$

    ⇒$x=y+2$   ............(2)

∴$2y=y+2$

⇒$y=2$

∴$x=2+2=4$

∴ The no. is (4×10)+2 = 42

Answer 2

Answer:

refer to the above attachment for the solution.