what is the final temperature of amixture containning 25 grams of ice at -20 degree celciusadded to water at room temperature 22oC mass of water is 50g

Below are four stages:

1. heat needed to raise T ice @ 20C to zero C.
2. heat needed to melt ice at zero to liquid water at zero.
3. heat needed to raise T ice at zero C to final T.
4. heat lost by 20 degree water to final T.

[mass ice @ 20 x specific heat solid ice x (Tfinal-Tinitial)] + [mass ice @ zero C x heat fusion] + [mass melted ice at zero x specific heat water x (Tfinal-Tinitial)] + [mass warm water x specific heat water x (Tfinal-Tinitial) = 0