This would be much, much, much easier if you told us
what numbers you do have on each side of the scale now.
The idea (probably) is that the scale is balanced when
the numbers add up to the same amount on both sides.
So you need to put some numbers in the blanks that will either
add more to the side that has less, or subtract some from the side
that has more, to make both sides equal.
We want to find miles per hour.
Speed is distance over time.
So take 10 miles (distance) / 3 hours (time)
This is the same as 10/3.
10/3 = 3 and 1/3
Therefore, the girl is going 3 and 1/3 miles per hour.
30 M&Ms
1) Gathering the data
12-ounce bag of trail mix = 18 M&Ms
20-ounce bag=?
2) Assuming that the M&Ms are placed in following a constant rate we can write the following proportion:
12 --------------- 18
20 --------------- y
<em>Cross multiplying it due to the first property of proportions</em>
<em />
12y =20 x 18
12y = 360
y=30
3) So, I'd expect to find 30 M&Ms at a 20-ounce bag of trail mix.
44 it's above .5 so you round up!