Answer:

Step-by-step explanation:
I am going to say that:
Mary's amount is x.
Ashley's amount is y.
Oscar's amount is z.
Mary has at least 3 times the amount of cash that ashley and oscar have combined
Ashley's and Oscar's combined amount is y + z.
3 times this amount is 3(y + z).
At least 3 times means that z is equal or greater than 3(y + z).
So

Answer:
2 and 13/60
Step-by-step explanation:
First, we must create a common denominator in the fractions. For the given denominators, it would be 60, so 3/4 would be 45/60 and 8/15 would be 32/60. From here, we can just subtract and get 2 and 13/60.
Hope this helps!
Answer:
The correct answer is "$5000".
Step-by-step explanation:
The given values are:
Two investments totaling,
= $47,500
Annual income,
= $3000
One investment yields per year,
= 9%
Other yield,
= 6%
Let,
- The amount invested in 9% will be "x".
- The amount invested in 6% will be "
".
Now,
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 