Teddy has two sisters. One of them is 3 years younger than Teddy, the other one is 7 years younger than her only brother. How ol
2 answers:
Given:
Teddy has two sisters. One of them is 3 years younger than Teddy, the other one is 7 years younger than her only brother.
To find:
The age of older sister at the time when the younger sister was born.
Solution:
Let the age of Teddy be x.
One sister is 3 years younger than Teddy.
Age of one sister = x-3 years
The other one is 7 years younger than her only brother. It means other sister is 7 years younger than Teddy.
Age of other sister = x-7 years
Clearly (x-3) > (x-7). So, difference between the ages of sisters is
Therefore, the age of older sister is 4 years when the younger sister was born.
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Answer:
11,880 different ways.
Step-by-step explanation:
We have been given that from a pool of 12 candidates, the offices of president, vice-president, secretary, and treasurer will be filled. We are asked to find the number of ways in which the offices can be filled.
We will use permutations for solve our given problem.
, where,
n = Number of total items,
r = Items being chosen at a time.
For our given scenario and
.
Therefore, offices can be filled in 11,880 different ways.