Question

Bob has B marbles in his marble collection. After Bob got another 15 marbles, he gives away 1/5 of his marbles. Write an expression for the number of marbles that Bob now has. Explain your reasoning.

Answer 1

Answer:

$\frac{B}{5} + 3$

Step-by-step explanation:

B: number of marbles

Bob got 15 marbles: $B+15$

Bob gives away 1/5 of his marbles. So, let's multiply our first expression by 1/5

$(B+15) X\frac{1}{5}$

Next, apply the distributive property of multiplication

$\frac{B}{5} + \frac{15}{5} = \frac{B}{5} + 3$

To the initial B marbles that Bob has, plus 15 aditional marbles he got later, we multiply it by 1/5 applying its distributive porperty to obtain the number of marbles that Bob now has