Habitat temperature

Question
After seeing some the answers and advice on this site, I replaced a stick-on thermometer in my daughter's 10 gal. gecko tank, with a digital probe type.  I think we are okay but I was surprised at the variations in temperature.  With the probe on the floor inside the hot hide: 92.4  Probe on the floor outside the hot hide: 90.2  Probe suspended about 3" off the floor on the hot side: 76  Probe on the floor of the cool side: 74.7  We use an under-tank heater and during the day add a heat lamp.  Is this a healthy range of temps?

Answer
 Actually, I would ditch the undertank heater since all heating should come from above.
 A wide range of temperatures is great, it allows the gecko to properly thermoregulate.  I would keep a nice range like that for the comfort of your daughter's pet.