Answer:
120
Step-by-step explanation:
Lets find the numbers multiples of 6 that are in the range from 104-140:
108, 114, 120, 126, 132, 138
Now out of these lets find which is divisible by 15
[tex]\frac{108}{15}=7.2\\\\\frac{114}{15}=7.6\\\\\frac{120}{15}=8\\\\\frac{126}{15}=8.4\\\\\frac{132}{15}=8.8\\\\\frac{138}{15}=9.2[/tex]
120 Is the only solution in this set which is also equally divisible by 15, making it the answer.