Bella spent 4/7 of her money on a dictionary and 3 identical books. She spent 1/6 of the remainder on a journal that cost $7. a) How much did she spend on the dictionary and 3 books? b) If 3/8 of the cost of the dictionary was the same as 1/2 of the total cost of 3 books, how much did each book cost?

a) 9.33$

b) 1.33$

Step-by-step explanation:

a)

To solve the problem, let's call

= the money that Bella has at the beginning

the price of a dictionary

the price of one book

the price of the journal

Here, Bella spent 4/7 of her money to buy a dictionary and 3 books, so

(1)

Then she spent 1/6 of the remainder (which is ) to buy the journal so

(2)

So from this second equation we can find m, the money that she has at the beginning:

So the amount that she spent for the dictionary + the 3 books is

b)

Here, we are told that

3/8 of the cost of the dictionary was the same as 1/2 of the total cost of 3 books

Which can be rewritten as an equation as follows:

This means that we can rewrite the cost of the dictionary by re-arranging this equation as:

Substituting into eq.(1) of part a),

And from this, we can find b, the cost of each book:

0.16 or 16%

step-by-step explanation:

lets take a coin for example.

if you toss it twice, it has a 1/4 chance of landing on heads both times because 1/2 * 1/2 is 1/4.

with the cards, the chance of picking dog is 0.4. having two people pick one is like picking a card twice in a row. so 0.4 * 0.4 is 0.16, or 16%