Convert 400 seconds into minutes, rounded to two decimal places.

• A. 6.50 minutes
• B. 6.25 minutes
• C. 6.67 minutes
• D. 7.00 minutes

Answer: (C)

You convert seconds to minutes by dividing by 60, since there are 60 seconds in a minute. So 400 seconds equals 400 ÷ 60 = 6.666... minutes. When rounding to two decimal places, look at the third decimal digit; it’s 6, so you round the second decimal up. This gives 6.67 minutes.

Another way to see it: 6 minutes and 40 seconds is 6 + 40/60 = 6 + 0.666... = 6.666..., which rounds to 6.67. The other values would correspond to different total seconds (390, 375, or 420), not 400.