9514 1404 393
Answer:
60 hours
Explanation:
We want Joanna's total savings to be ...
bank account + gift + earnings = 1000
300 +100 +10h = 1000
10h = 600 . . . . subtract 400
h = 60 . . . . . . . .divide by 10
Joanna needs to babysit for 60 hours to earn the money she needs.