Final answer:
Vernon's baby boy currently weighs 3⅗ kg and needs to gain 1400g to reach the target weight of 5½ kg. Gaining 190g each week, it will take him approximately 7.36 weeks, which we round up to 8 weeks.
Step-by-step explanation:
The student is asking how many weeks it will take for Vernon's baby boy, who currently weighs 3⅗ kg, to reach a weight of 5½ kg if he gains 190g per week. To solve this, we first convert the weights into the same unit (grams) and then calculate the difference between the desired weight and the current weight. Afterward, we divide that difference by the weekly weight gain to determine the number of weeks.
- Convert the baby's current weight to grams: 3⅗ kg = 3600 + ½(1000) = 3600 + 500 = 4100g.
- Convert the target weight to grams: 5½ kg = 5000 + ½(1000) = 5000 + 500 = 5500g.
- Calculate the weight the baby needs to gain: 5500g - 4100g = 1400g.
- Calculate the number of weeks needed: 1400g ÷ 190g/week = approximately 7.36 weeks.
Since partial weeks are not usually counted in full, we can round up to the nearest whole number. Therefore, Vernon's baby boy will reach 5½ kg in 8 weeks.