What is 8% of 150 when you multiply it

Adriano loves anime and collects toys from his favorite series. each month he gains 4 toys. if adriano has 3 toys when he starts collecting, how many does he have after 4 months

What is the value of x in the diagram below?

Scrub a dub toothbrushes are $4.00 each. there is a 10% discount, but there is also a 6% sales tax after the discount is applied. what is the new price after tax? round to the nearest penny