7 * 0.5 + 3 * 0.8 = 3.5 + 2.4 = 5.9
<span>5.9/10 X 100 = 59%
</span><span>59% concentration of new mixture</span>
That sentence in math means:
X = 0.25 * 825
X = $206.25
Given:
The scale of a map is
.
The distance between two buildings is 60 miles.
To find:
The distance between the given building on the map.
Solution:
We have,

It means, 80 miles in real life =
on the map.
1 mile in real life =
on the map.
60 mile in real life =
on the map.
=
on the map.
=
on the map.
Therefore, the buildings are
apart on the map.
B)70 because sina=cos(90-a)