Ответ:
Объяснение:
Betty is seventeen. 17
Mark is Betty plus two nineteen. 17+2=19
Ann is Mark minus ten nine. 19-10=9
John is Ann plus two eleven. 9+2=11
Sue is Ann plus John twenty. 9+11=20
Bob is Sue minus Betty three. 20-17=3
Wendy is Bob plus twelve fifteen.3+12=15
Sam is Wendy plus three eighteen. 15+3=18
Pete is Sam minus five thirteen. 18-5=13.