308.3 divided by 15 could be estimated by rounding 308.3 down to 300 and dividing that by 15:
300
----- = 20
15
First you'll need to get the same denominator. So instead of 3/5 and 3/8 you'll have 24/40 and 15/40. Now that we've changed the value of the denominator, the 40/40 will now represents the 1 hour that Jenny has before bedtime. So you add 24/40 and 15/40 and get 39/40. 39/40 stands for the time that Jenny has already spent brushing her teeth and texting her friend all together. Since the 1 hour is 40/40 subtract 39/40 from it to get 1/40. 1/40 is equal to the rest of the time Jenny spends reading or 1.5 minutes.
Answer:
The number is 623.
Step-by-step explanation:
