First, you have to make them into decimals to make it easier. 2/8 equals 0.25.
1/5 and 2/10 equal 0.2. 0.2+0.2+0.25 equals 0.65 so if you suppose Jon's money is 1 dollar, he has 35 cents left. In a fraction, 0.35 is 35/100. If you simplify 35/100, it's 7/20.
Answer: Jon has 35/100 or 7/20 or his money left.
I hope it helps!
Given rate is = 7% or 0.07
Total amount needed = $12000
Time = 4 years
Here, the deposit is compounded semiannually, means twice per year and this gives 8 annual compounding periods in 4 years.
The equation becomes:
P= 
P = 
Solving it, we get P = $ 9112.93
Hence $9112.93 should be deposited today.
Hey!
First, let's write the problem.

We know that,

, so let's apply that

We have to add,


We know that

, so let's apply that.

Subtract.

Our final answer would be 7!Thanks!
-TetraFish
(a) 32 orange marbles
the ratio of red : blue = 18 : 48 = 3 : 8 ( in simplest form )
the ratio of green : orange = 3 : 8 ( equal ratio )
divide green by 3 to obtain 1 part of ratio then multiply this value by 8 to obtain the amount of orange marbles
3 parts → 12
8 parts → 12 ×
= 32 orange marbles