Go Where Ya Need To!
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Brothers
& sisters |
Joan has the same number of sisters as she has
brothers, but her brother Alex has twice as many sisters as he has
brothers. If their family has fewer than 10 children how many of
them are boys and how many are girls? |
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Answer: 4
girls and 3 boys. Joan has the same number of sisters as
brothers, we need to test only the combinations in which Joan has the
same numbers of sisters and brothers up to 4 each. If Joan has 5
sisters and 5 brothers, the family has 10 children Once Joan's
siblings are determined, we know that Matt has one more sister than
Joan and one less brother. We need to check only that the
number of Matt's sisters is twice that of his
bothers. |
The
Opposite Hands |
When the hour hand on a clock is between 12:00 and
1:00, during which 1-minute time interval are the minute hand and the
hour hand pointed in exactly opposite directions? |
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Answer: ...between 12:32 and 12:33. To be opposite the hour
hand must be between 6 &7. The hour hand moves five 1-minute
marks during the same time that the minute hand sixty 1 minute
marks. When the hour hand is on the first minute mark, the time
is about 12:12. At the 2-minute mark, the time is about 12: 24,
and at the 3-minute mark, the time is about 12:36. At some point
between the 2 & 3 minute mark, the minute and hours hands are
opposite each other. |
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