Answer:

Step-by-step explanation:
we know that
To find out how many pencils the teacher has left, subtract the quantity of p*s from 54
so

1 and 3; 2 and 4 (sorry if I was too late to answer you)
Answer:
$12
Step-by-step explanation:
Since she has $16 left, this means she spent $84. ($100-$16=$84)
Then, since she bought the same give for 7 of her friends, divide:
84/7=12.
This means that each gift cost $12.