Question

Several guys went to eat lunch at Subway

Answer 1

Answer:

Joseph's bill was $9.6.

Step-by-step explanation:

Given:

Number of cold drinks  = 4

Number of subway sandwiches = 7

Total cost of cold drinks and sandwiches = $21.60

The sandwiches cost  twice as much as the cold drinks

To Find:

How much  was Joseph's bill = ?

Solution:

Let the cost  of one cold drink be x

The cost of  sandwich be y

The sandwiches cost  twice as much as the cold drinks

then

y = 2x--------------------------------------(1)

Now the total amount can be represented as

4x+7y =21.60-----------------------------(2)

Substituting (1) in (2)

4x+7(2x) =21.60

4x+14x =21.60

18x =21.60

$x = \frac{21.60}{18}$

x = 1.2--------------------------------------(3)

The cost of one cold drink is $1.2

On substituting (3) in(1)

y = 2(1.2)

y = 2.4

The cost of one sandwich is $2.4

Now ,Joseph and  his date had two cold drinks and three Subway sandwiches.  So Joseph bill will be

=>$( 2 \times \text{ cost of one cold drink} )+ (3 \times \text{ cost of one subway sandwich})$

=>$(2 \times 1.2) + (3 \times 2.4)$

=>(2.4) + (7.2)

= 9.6