Respuesta :

Firstly, round 63 and you get 60, then, round 42 and you get 40. Finally, add 60 and 40. Your answer will be 100. 

Thank You, 
    Helpingothers


natasha16
the estimate of 63+42 is 100 because you round to the nearest tenth 

63→ 60 & 42→ 40 so you add them together and you get 100