The Crews family went on a day trip to Nashville. For lunch they paid $7.50 for each adult meal and $5 for each child meal for a total of $65. For dinner the family paid $10.50 for each adult meal and $5 for each child meal for a total of $77. How many adults and how many children were on the trip?

Number of adult were on the trip = 4

Number of child were on the trip = 7

Step-by-step explanation:

Let the Number of adult were on the trip = x

Let the Number of child were on the trip = y

As given,

For lunch they paid $7.50 for each adult meal and $5 for each child meal for a total of $65.

⇒7.50x + 5y = 65            ...........(1)

Also,

For dinner the family paid $10.50 for each adult meal and $5 for each child meal for a total of $77.

⇒10.50x + 5y = 77            ...........(2)

Now,

Subtract equation (2) from equation (1) , we get

10.50x + 5y  - ( 7.50x + 5y ) = 77 - 65

⇒10.50x + 5y  - 7.50x - 5y  = 12

⇒10.50x - 7.50x  = 12

⇒3x = 12

⇒x = = 4

⇒x = 4

Now,

Put the value of x in equation (2) , we get

10.50(4) + 5y = 77

⇒42 + 5y = 77

⇒5y = 77 - 42

⇒5y = 35

⇒y = = 7

⇒y = 7

∴ we get

Number of adult were on the trip = x = 4

Number of child were on the trip = y = 7

SI=(P*R*T)/100

P=2000

R=1.5

T=6

SI=(2000*1.5*6)/100

=(2000*9)/100

=180

Neil will earn interest of 180

Cost of 7 gallons=$24.50

Cost of 1 gallon=24.50/7=3.5

Cost of 15 gallons=15*3.5=52.5

Cost of 15 gallons will be $52.5

For 1 flavor there are 9 topping

Therefore, for 5 different flavors there will be 5*9 choices

No of choices= 5*9

=45 

The answer is in the image 

The solution is given in the image below

The wood before starting =12 feet

Left wood=6 feet

Wood used till now=12-6=6 feet

Picture frame built till now= 6/(3/4)

=8 pieces

Therefore, till now 8 pieces have been made.

30% of 420 are first year students

first year students = (30/100 )*420

=126 students

Student who are not in first year = 420-126

=294 students  

Given height of gymnasium is 5/6 height of 30 foot ball

therefore height of gymnasium=5/6 * 30

=25 feet

Cost before sale tax=$46.00

Cost after including tax=$48.76

Sale tax=$48.76-46.00

=$2.76

we know,

sale tax=((sales tax rate)/100) * cost before sale tax

2.76=((sales tax rate)/100) *46.00

sale tax rate=(2.76*100)/46

                   =276/46

                    =6%

There fore sales tax rate=6%