Astudy was conducted to estimate the infant birth weight (grams) using three explanatory variables, smoking mother (x1=1 if smoked; =0 if not), mother’s pregnancy weight gain (x2 : pound) (mother_gain_wt) and the number of prenatal visit (x3: visit). predict the infant birth weight of mons who did not smoke, gained 10 lb during pregnancy and visited the doctor’s office 3 times before the baby was born.