Resposta:

Explicação passo a passo:

2,4888...

x=2,48888...

10x=24,8888...

100x=248,8888...

100x-10x=248,888...-24,8888...

90x=224

x=224/90

1,727272...

y=1,727272...

100y=172,727272...

100y-y=172,727272...-1,727272...

99y=171

y=171/99

2,4888...+1,727272...

224/90+171/99=

2464/990+1710/990=

4174/990