Question 939625
St + Mt=26
S(2) + m(2) = 26
S + M=13----EQ 1

M-S=12----EQ 2

SOLVE M USING 2 EQUATON BY SUBSTRACTION 

M=12.5KM/HR

SUBSTITUTE M TO EQ 1 TO SOLVE S

S=0.5KM/HR----------ANSWER====