3. The average of two numbers is 55. If their positive difference is 64, then determine the two numbers algebraically.

the numbers are 41 and 23

Step-by-step explanation:

Given data

let the numbers be x and y

x+y/2= 55

cross multiply

x+y= 1101

positive difference is 64

x-y= 642

solve 1 and 2

x+y= 110

x-y= 64

from 1

x= 110-y

put the value of x in 2

110-y-y=64

110-2y=64

110-64=2y

46=2y

y= 46/2

y=23

put y= 23 in 2

x-23= 64

x= 64-23

x=41

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 answer is in the image 

y=2x+15

where y=Value of coin

x=Age in years

Value of coin after 19 years=2*19+15

=$53

Therefore, Value after 19 years=$53

Salesperson will make 6% of 1800

=(6/100)*1800

=108

Salesperson will make $108 in $1800 sales

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.

Salesperson will make 6% of 1800

=(6/100)*1800

=108

Salesperson will make $108 in $1800 sales

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