Tom and lisa each had a birthday party at hurricane harbor last weekend . the cost of admission was $137.50 for 13 children and 2 adults at toms party. at lisa’s party the admission was $103.50 for 9 children and 2 adults

Per child admission costs $8.5

Per Adult admission costs $13.5

Step-by-step explanation:

Let x be the amount of admission per child and y be the amount of admission per adult

For Tom's party:

13x+2y=137.50      (Equation 1)

For Lisa's Party:

9x+2y=105.50       (Equation 2)

Using Elimination Method:

Add Equation 1 & 2

13x+2y=137.50

9x+2y=105.50  

-    -   = -         (Change of Signs)

4x+0y=34.00      

x=34/4

x=8.5

Putting the value of x in Equation 2

13(8.5)+2y=137.50

110.5+2y=137.50

2y=137.50-110.50

2y=27

y=27/2

y=13.5

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)

answer:

what is your question that you ask

step-by-step explanation: