1.
The rate at which Leonard bought was 2 packs per x dollars,
that is his buying rate was (2 packs)/(x dollars)=2/x (p/$)
2.
with 1 $ Leonard buys 2/x packs
then
with 5 $ Leonard buys (2/x)*5 = 10/x packs.
Answer: 10/x packs
Hey there mate :)
Please check the attached image for answer.
Simplify (we cannot solve if there is no equals)
6s^3(5s^2)(3s^4)
multiply the coefficients, add the exponents since the bases are the same
(6*5*3) s^(3+2+4)
90 s^(9)
Adam took 7 pieces so subtract it from the total.

He divided the rest to his 3 children

Each child recieved 2 candies.