Answer:
The amount invested at 4% is $20,500 and the amount invested at 10% is $500
Step-by-step explanation:
Let
x -----> the amount invested at 4%
(21,000 -x) ----> the amount invested at 10%
we know that
The interest of the amount invested at 4% plus the interest of the amount invested at 10% must be equal to $870


so

Solve for x





therefore
The amount invested at 4% is $20,500 and the amount invested at 10% is $500
Eli will finish first.
Use 8/10 and 10/12. This represents how many spring rolls over how many minutes. Make your equations like this: 8/10 = 40/x and 10/12 = 40/x. Find x, which will give you the minutes it takes them to make 40 rolls.
You get x = 50 for the first one and x = 48 for the second. Nora makes 40 rolls in 50 minutes, and Eli makes 40 rolls in 48 minutes. Eli is faster.
Hope this helped! Please mark me brainliest!
Answer:
look at the picture
Step-by-step explanation:
This photo is the explanation