Chapter 7.4, Problem 43E

To determine

To find:the percent of the blue marbles present in the bag

Answer to Problem 43E

The new percent of the blue marbles in the bag is 50%

Explanation of Solution

Given information:

There are 35% blue marble in a bag, bag contain 20 marble, and then 6 blue marbles are added into the bag.

Calculation:

Total number of the marbles in a bag is 20.

Blue marbles present in a bag (in percent) is 35%

So, blue marbles present in a bag (in number) is

  $\begin{array}{l}\text{35\% of 20 }\\ =\frac{35}{100}\cdot 20\\ =7\text{marbles}\left[\text{write percent in whole number}\right]\end{array}$

Again, 6 marbles are added into bag

Therefore the total number of blue marbles in bag is $7+6=13$

And, the total number of marbles in bag is $20+6=26$

The new percent of blue marbles in bag after adding 6 blue marbles is $\begin{array}{l}\frac{13}{26}\cdot 100\left[\text{ write the formula of percent}\right]\\ 50\%\left[\text{write it into percent}\right]\end{array}$

Hence, the percent of the blue marbles in the bag is 50%