A rental car cost $20 per day, and a room cost $50 per day, for how many days can a room and car be rented, so that the total cost does not exceed $350

  5

Step-by-step explanation:

The total cost per day is $20 +50 = $70. Then the number of days that expenditure can be made on a budget of $350 is ...

  $350/($70/day) = 5 days

Step-by-step explanation:

let number of days =x

(20+50)x≤350

70 x≤350

x≤350/70

or x≤5

He can rent both at the most 5 days.