Hi Terry,
Your throttle will work fine, but the battery gauge LEDs will not function correctly if the voltage does not match the battery.
I have a 36V throttle
(24V and 48V are usually marked on the throttle housing but the 36V has no markings) and I only use 25.9V or 51.8V LiPo packs with it.
On the 25.9V pack I just have the single red LED illuminated, and on the 51.8V pack I have all three LEDs illuminated, regardless of whether the pack is fully charged or almost completely exhausted.
The throttle control does get a bit warm on the 51.8V pack but it has survived over two years so far, but I'm not sure whether the battery gauge on a 24V throttle would have lasted this long on a 51.8V pack.
Even when the correct voltage throttle unit is used, the battery gauge, which was initially intended for use with lead acid batteries, is somewhat inaccurate with lithium battery packs.
I therefore use a Turnigy Watt Meter to measure the actual energy being consumed, and I simply subtract the Ah used from the battery's Ah rating to give a pretty good indication of how much capacity I still have left.
Alan