Question

determine the final temperature if you mix 1 kg of water which is 40 degree Celsius with one kg of water with which is at 60 degree Celsius​

Answer 1

We know that final temperature (f) = (m1t1+m2t2) / (m1+m2)

here m1 = 1 kg

m2 = 2 kg

t1 = 40

t2 = 60

so f = (40+60)/2

=50° C

Answer 2

$if \: we \: mix \: 1kg = 40 {}^{degree} \\ one \: kg = 60 {}^{degree} \\ temperature (t)= \frac{m1t2 + m2 t2}{m1 + t2} \\ t = \frac{1 \times 60 + 1 \times 40}{1 + 1} \\ t = \frac{60 + 40}{2} \\ t = \frac{100}{2} \\ t = 50 \\ t = 50 {}^{degree}c$