I belive the answer is d I think I am studying the same thing also
Let the actual value of the stool be x.
So if the carpenter sells the stool x rupees he neither loses, now wins anything.
67.50 is the value x - 10% of x, that is:
67.50=x-0.1x
67.50=0.9x
x=67.50/0.9=75 (rupees) is the actual value of the stool.
Selling the stool for 82.50 rupees, the carpenter clearly would make a profit, say of y% of that actual value, that is y%*75.
So using the same method:
82.50=75+y%*75
y%*75=82.50-75=7.5
we can make the calculations, but clearly 7.5 is 10% of 75
Answer: 10% gain.
Robin has to go shopping for her brother's birthday.
She already bought "x" presents for him.
The next day, Robin bought "2" more presents for him just in time for his birthday.
When she got home and celebrated his birthday, her beother opened, in total, "9" presents.
--- What is the number of presents that Robin had originally purchased? ---
Answer:
1/22
Step-by-step explanation:
assuming that the marbles drawn are not replaced:
P(red) = 3/12 or 1/4
P(green) = 4/11
P(blue) = 5/10 or 1/2
multiply the probabilities together:
1/4 x 4/11 x 1/2 = 1/22
