the vet said that smell and taste goes first I'm feeding her soft food
We thought we were losing Annie at about that age -- it turned out she had fixable dental problems and also a benign cyst pressing on her internal organs that was drained. After recuperating from her treatments, she was back in business. You just never know ...
Phoenix is right...it's impossible to tell when she might pass on.
Has she seen a veterinarian recently? Has any bloodwork been done that might help to identify her general state of health?
Why do you think she has lost her sense of smell and taste?
There is no way of knowing when your cat is going to die. they don't come with exasperation dates. my cat, Tiger, is 20 1/2 years old she sleeps a lot, mainly during the day. cats age faster then us in a year. the 1st year for a cat is about 14years, every year after is 4 years. Tiger is in her 90's in cat years. Mindy is about 74, so its no wonder she sleeps a lot. Think about us humans as we get up there in age, we tend to sleep a lot or at least that's what I've noticed about my grand parents (they're in there 90's) Tiger eats a little here and there and still runs (although she's a little slower now vs when she was younger). She still runs up to any family member and tags them in the foot (usually with claws) and then takes off running. she has does this since she was a kitten, I call it counting coo.
I don't have any advice for Mindy's loss of smell/taste. my cats haven't had that problem