When a +1/+1 counter is placed on a Gray Ogre and the creature's power increases, what is its new power and toughness?

A Gray Ogre is a creature with a printed power and toughness of 2/2. When a +1/+1 counter is placed on it, the counter effectively increases both its power and toughness by 1. This means its power goes from 2 to 3 and its toughness also increases from 2 to 3, resulting in a new power and toughness of 3/3.

This basic rule of +1/+1 counters states that for each counter placed on a creature, both the power and toughness of that creature are increased by the amount specified by the counter—in this case, 1 for the +1/+1 counter. Therefore, the newly updated stats for the Gray Ogre accurately reflect this increase, making its power and toughness 3/3.