Answer:
6.
Step-by-step explanation:
We can start by defining a couple things.
x = amount of nickels
y = amount of dimes
Since he has the same amount of each, we can say this.
x = y
And because we know it totals 0.90, we can say this.
0.05x + 0.10y = 0.90
then, we substitute and get this.
0.05x + 0.10x = 0.90
Simplify.
0.15x = 0.90
Divide both sides by 0.15.
x = 6
So we have 6 nickels, and they both are the same, so we have 6 dimes.
In the given diagram, the traingles USW and UTV are similar triangles and thus the following ratio equality applies to them.
..........(Equation 1)
Checking the diagram given, we see that:
VT=y, WS=22, VU=8, ST=x-2
WU=WV+VU=12+8=20
TU=5
SU=ST+TU=(x-2)+5=x+3
Thus, substituting the required values in (Equation 1) we get:

Now, as can be clearly seen, to find y we will use the first two ratios as:


In a similar manner, to find the value of x we can use the last two ratios:

After cross multiplication we get:

Which can be simplified as:

Thus, 
Therefore, the required answer is:
x=9.5 and y=8.8
6 inches of yarn make 1 bracelet.
5 feet of yarn make how many bracelets?
1 foot = 12 inches
5 feet = 12 * 5 inches = 60 inches
6 inches of yarn make 1 bracelet
60 inches of yarn make x bracelets
6/1 = 60/x
Cross multiply
6x = 60
x = 10
60 inches yarn make 10 bracelets.
After the second, it will be 50, after the third it will be 20, and after the fourth it will be 8. The answer is C
Hope this helps!