Physics problem?

Question

A 600g sample of water at 90 Celsius is mixed with 400g of water at 22 Celsius. Assume no heat loss to the surroundings. What is the final temp of the mixture?

Answer 1

You can use weighted average for this...But you'll need to use absolute temperatures

0.6 * (90 + 273) + 0.4 * (22 + 273) = 335.8 K = 62.8 C
OR
0.6 * (90 - 22) + 22 = 62.8 C