Respuesta :
Answer:
1 year ago
Step-by-step explanation:
One year ago, John would have been 6 and his grandfather would have been 54. 6 times 9 is equal to 54.
When John was 6, his grandpa was 54. This can be determined by basic subtraction. 6 * 9 = 54. If he is 7 right now, it was a year ago since his grandpa was 9 times his age. So the answer is a year ago. Hope it helps!