Solution:

84years old


The first equation (365g = 52s) can be approximated by
7g = s.

As before, the other two equations are
12g = m
g + s + m = 140.

The above system of 3 equations in 3 unknowns (g, s and m) can be simply solved as follows.
g + 7g + 12g = 140 or 20g = 140.
m = 12g = 12 × 140 / 20 = 84.

So, Grandpa is 84 years old.

Solution:

Hockey Stick $49.50 & ball $0.50

Solution:

Never

Explanation:
In the question, the distance of x miles is given at a particular moment. The middle car is running at that time at 50 MPH. The distance will keep increasing with time as three are running at different speeds. It will increase by x miles every hour till a certain point of time and then it will start decreasing till the fastest car meets the slowest again.

As per question, all the cars stop then. Thus, the distance will never be x miles again.

Solution:

Tilt the barrel until the fruit juice barely touches the lip of the barrel. If the bottom of the barrel is visible then it is less than half full.If the barrel bottom is still completely covered by the fruit juice, then it is more than half full.

Solution:

They are matched as shown in the picture below.

Solution:

She is near the trunk of the tree as shown below.

Solution:

Treasure Map Is Hidden Inside The Hanging Room Floor.

Explanation.
Just reverse the text "roolF mooR gnignaH ehT edisnI neddiH sI paM erusaerT".

Solution:

The Stars

Solution:

Old password : altered

New Password : distinct

Solution:

2 degree below zero

Solution:

See the colored sticks in the picture. We have moved those sticks in the position given in the second image corresponding with the color.