Find the ratio
Answer: (2) 13: 10
Let the first number and second number be X and Y.
One-half of a certain number is equal to 65% of 2nd number.
Then X/2 = Y x 65/100
X = Y x 13/10
X/Y = 13/10
Then the ratio of 1st and 2nd number is 13: 10.
Hence, the correct answer is option (2) 13: 10.