Question

use the measurement scales to fill in the tables and answer the questions.
minutes
0 1 2 3 4 5 6 7 8 9 10

0 60 120 180 240 300 360 420 480 540 600
seconds
hours
0 1 2 3 4 5 6 7 8 9 10

0 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600
minutes
①
hours minutes
1 60
4 240
8 480
11 660
②
minutes seconds
1 60
5 300
10
20
③ zac worked on his spelling for 9 minutes last night and 8 minutes this afternoon. how many seconds did he work? answer: ______ seconds
④ etons baby sister took a nap for 2 hours and 22 minutes yesterday and 1 hour and 35 minutes today. how many more minutes did she sleep yesterday than today? answer: ______ minutes
try this
⑤ how many seconds did etons baby sister sleep all together? answer: ______ seconds
practice
⑥ 945 + 1,055 = ______
⑦ 2,953 + 4,471 = ______
⑨ 3,649 + 3,649 = ______

Explanation:

Step1: Calculate total minutes for Zac

Add minutes Zac worked last night and this afternoon. $9 + 8=17$ minutes.

Step2: Convert minutes to seconds for Zac

Since 1 minute = 60 seconds, then $17\times60 = 1020$ seconds.

Step3: Calculate total minutes for Eton's sister each day

Yesterday: 2 hours and 22 minutes. 2 hours = $2\times60=120$ minutes, so total yesterday is $120 + 22=142$ minutes. Today: 1 hour and 35 minutes. 1 hour = 60 minutes, so total today is $60+35 = 95$ minutes.

Step4: Find difference in minutes for Eton's sister

Subtract today's minutes from yesterday's. $142-95 = 47$ minutes.

Step5: Calculate total minutes for Eton's sister in two - days

Add yesterday's and today's minutes. $142 + 95=237$ minutes.

Step6: Convert total minutes to seconds for Eton's sister

Since 1 minute = 60 seconds, then $237\times60=14220$ seconds.

Step7: Calculate 945 + 1055

$945+1055=(900 + 45)+(1000+55)=(900 + 1000)+(45 + 55)=1900+100 = 2000$.

Step8: Calculate 2953+4471

$2953+4471=(2000 + 900+50 + 3)+(4000+400+70+1)=(2000 + 4000)+(900 + 400)+(50 + 70)+(3 + 1)=6000+1300+120 + 4=7300+120+4 = 7420+4=7424$.

Step9: Calculate 3649+3649

$3649+3649=(3000 + 600+40 + 9)+(3000+600+40+9)=(3000 + 3000)+(600 + 600)+(40 + 40)+(9 + 9)=6000+1200+80+18 = 7200+80+18=7280+18 = 7298$.

Answer:

1. 1020
2. 47
3. 14220
4. 2000
5. 7424
6. 7298