87% OC adults figured this out. Can you?

Question

9 fish are 5 months old. 12 fish are 7 months old. How many full months from now will the age of the 21 fish surpass 20 months old?
THe math textbook is 1in thick and weighs 6 oz. How many of these books can be placed on the shelf of a 3ft long bookshelf that can support 10 lbs.
In a room, each 22 liters of air weighs 29 grams. Each liter is 1000 cubic meter of air in that room weigh Express answer tonearest whole gram
A day can be evenly divided into 86400 periods of 1 second; 43200 periods of 2 sec; or in many other ways. In total, how many ways are there to divide a day into n periods of m seconds, where n and m are positive integers
What is the length of the longest stick that can fit into a right rectangular prism measuring 3 ft by 4 ft by 12 ft
Will will fill in the three blanks in the expression __ - ( __ - __ ) using each of the 3 numbers 2,3, and 5 once. How many distinct simplified values are possible
What is the sum of the the 2 values of x when (x+3)squared=121

Please aswer the questions too. thank u sooo much! and plz plz plz dont say do it urself. its a waste of my time and urspeople who do thatjust want free points and i will report u

Answer 1

I guess I'm one of the 87%... Nothing too difficult. Oh and since your question asked only whether or not I could solve it, I didn't bother putting down the answers ^_^

Answer 2

1. If you mean all the fish must be at least 20 months old, it will take 15 months (then the 9 will be 20 months and the 12 will be 22 months); if you mean they must be more than 20 months, and the 9 fish are exactly 5 months old (not 5 months and 1 day) then it will take 16 full months.

2. Can hold 36 by length, can support 160/6 = 26 2/3 by weight, so we can put 26 books on it.

3. I think you're missing the size of the room. Per cubic metre the weight of air is 1000/22 * 29 = 1318.18 g, multiply this by the number of cubic metres and round to the nearest integer to get your answer.

4. 86400 = 24*60*60 = 3.2^3.(2^2.3.5)(2^2.3.5)
= 2^7 . 3^3 . 5^2 . 7
We can take m to be any factor, so we have 8 choices for the power of 2 (0-7), 4 choices for the power of 3, 3 choices for the power of 5 and 2 choices for the power of 7. So there are 8*4*3*2 = 192 possibilities.

5. The diagonal is 13 ft (3-4-5 and 5-12-13 triangles, or work out 13 = √(3^2 + 4^2 + 12^2)). So this is the longest stick that will fit, assuming we can't bend or break it. ;-)

6. 2 - (3-5) = 4; 2 - (5-3) = 0; 3 - (2-5) = 6; 3 - (5-2) = 0; 5 - (2-3) = 6; 5 - (3-2) = 4. So there are three distinct simplified values (0, 4 and 6).

7. (x+3)^2 = 121 => x + 3 = ±11 => x = -14 or 8, so the sum is -6.

Answer 3

1. Fish
The only way this problem is interesting is if you are talking about the ages of the fish all added together.


5 + 7 + 21m > 20
21m > 12
m > 12/21 = 0.38 months


2. Textbooks
36 textbooks could physically fit on the shelf,
but 10 lbs of books = 160oz = 160/6 = 26.7 => 26 books


3. Air
I think you need to tell us the size of the room or something.
If the room has size V cubic metres.
Then the mass of air = (V * 1000 / 22) * 29g.


4. Day
Getting the prime factors of 86,400, we find they are:

2 * 2 * 2 * 2 * 2 * 2 * 2 * 3 * 3 * 3 * 5 *5

There are seven 2's, three 3's and two 5's.

The number of different products we can get =
8 x 4 x 3 - 1 = 95.
(We can choose between 0 and 7 two's, between 0 and 3 three's, and 0 and two 5's. We subtract 1 for the 0,0,0 case.)

There is also the case of 1.

That makes 96 different sets of m and n.


5. Stick
The stick is the hyptoneuse of a right triangle of side 5 and 12. This is another well-known triangle (like 3,4 5) and is (5,12,13). Therefore the stick is 13ft long.


6. Blanks
Well there are six possible orderings so we can try them all out
2 3 5 = 4
2 5 3 = 0
3 5 2 = 0
3 2 5 = 6
5 2 3 = 6
5 3 2 = 4

Therefore there are only 3 distinct values: 0, 4 and 6


7. Sum
(x+3)squared = 121
x+3 = +/-11
x = 8 or x = -14
x1 + x2 = -6

Answer 4

1)13 months
2)26
3)i dont understand the third question.
4)7*3*2=42
5)13ft
6)3
7)-4