Question

Can come help me set up these problems. There two different problems.

Answer 1

Question 4:

Call the number of pennies $p$ and the number of nickles $n$. We know that:

$p+n=199$

and

$0.01p+0.05n=7.67$

Therefore, by substitution:

$p=199-n$

$0.01(199-n)+0.05n=7.67$

$1.99-0.01n+0.05n=7.67$

$0.04n=5.68$

$n=142$

$p=199-142=57$

There are 142 nickles and 57 pennies.

Question 5

$x+y=157$

$x-y=19$

$x=157-y$

$157-y-y=19$

$157-2y=19$

$2y=138$

$y=\frac{138}{2}$

$y=69$

$x=157-y$

$x=157-69=88$

The numbers are 69 and 88.