A ) 18 years old
B) 19 years old
C) 27 years old
add three to kris' age to find Pat's age
Explanation
Step 1
when Kris was 15 .how old was pat
find the rule
a) check if the difference between the ages is constant
[tex]\begin{gathered} \text{Pat's age - Kris' Age=} \\ 7-4=3 \\ 10-7=3 \\ 15-12=3 \\ y_4\text{-}15= \\ 22-x_5= \\ 26-23=3 \end{gathered}[/tex]it means Pat is 3 years older than Kriss
then
when Kris was .how old was pat
[tex]\begin{gathered} y_4\text{-}15=3 \\ y_4-15=3 \\ \text{add 15 in both sides} \\ y_4-15+15=3+15 \\ y_4=18 \end{gathered}[/tex]Step 2
when Pat was 22, How old was Kris
the difference between the ages is the same, 3
so
[tex]\begin{gathered} 22-x_1=3 \\ \text{subtract 22 in both sides} \\ 22-x_5-22=3-22 \\ -x_5=-19 \\ x_5=19 \end{gathered}[/tex]Step 3
when Pat was 30, How old was kris
replace
[tex]\begin{gathered} \text{Pat's age -Kris' age=3} \\ 30-\text{Kri's age=3} \\ \text{subtract 30 in both sides} \\ 30-\text{Kri's age-30=3-}30 \\ -\text{Kris'age =-27} \\ \text{Kris'age }=27 \end{gathered}[/tex]Step 4
wich choice best represents the rule
as we saw before,
add three to kris' age to find Pat's age
[tex]\text{Kris' age+3}=\text{Pat's age}[/tex]