Answer:
40 years
Step-by-step explanation:
Let Pamela's age be P, and Jiri's age be J
given:
"Pamela is 7 years older than Jiri"
mathematicallyL
Pamela's age = Jiri's age + 7 years, or
P = J + 7 (rearranging)
P - J = 7 --------------(eq1)
also given:
"sum of their ages is 87"
Pamela's age + Jiri's age = 87 years, or
P + J = 87 ----------(eq 2)
by elimination (eq1 - eq2)
(P - J) - (P + J) = 7 - 87
P - J - P - J = -80
-2J = -80 (divide both sides by -2)
J = (-80) / (-2)
J = 40
