Coco has a jar containing pennies and nickles. there is $9.20 worth of coins in the jar. if she could switch the number of pennies with the number of nickles, there would be $26.80 worth of coins in the jar. how many pennies and nickles are in the jar?

There are 520 pennies and 80 nickles.

Explanation:

According to the statement we can write the following equations:

0.01x+0.05y= 9.20   ①

0.05x+0.01y= 26.80  ②

x refers to pennies and y to nickles.

First, we have to isolate x in the first equation:

x= (9.20-0.05y)/0.01  ③

Then, we replace ③ in ② and solve for y:

0.05((9.20-0.05y)/0.01)+0.01y= 26.80

5(9.20-0.05y)+0.01y= 26.80

46-0.25y+0.01y=26.80

-0.24y=-19.2

y=-19.2/-0.24= 80

Now, that we have found the value of y, we can replace it in ③:

x=(9.20-(0.05*80))/0.01= 5.2/0.01= 520

(C) The children arrived first for the lottery.

Explanation:

The text says (The children assemble first) which it tells the answer.