Answer:
<em>19800 seconds, or 330 minutes, or 5 hours + 30 minutes</em>
Step-by-step explanation:
<u>Number Permutations</u>
We know the phone number has 7 digits, 4 of which are known by Mark. This leaves him 3 digits to guess with. We also know the last one is not zero. The number can be represented as
XXY
Where X can be any digit from 0 to 9 and Y can be any digit from 1 to 9. The first two can be combined in 10x10 ways, and the last one can be of 9 ways, this gives us 10x10x9 = 900 possible permutations.
If each possible number takes him 22 seconds, every possibility will need
22x900=19800 seconds, or 330 minutes, or 5 hours + 30 minutes
Answer:
Yes
Step-by-step explanation:
Yes they are because if you divide 18 by 3 you get six and if you divide 15 by 3 you get 5, so it simplifies to 6:3 which is the same as the ratio for rings
Answer:
the following are all equal
3/5 (x1)
6/10 (x2)
9/15 (x3)
12/20 (x4)
Step-by-step explanation:
at first solve first triangle with Pythagorean solving witch it c²=a²+b²
you have to change a bit so it will be c²-b²=a²
you start with 8 and 10 triangle and then you get line which is in the middle and yo udo just the same with triangle 8 and the solved side and you get x in the second triangle you have to use c²-a²=b²
if you're solving for the surface area of a rectangular prism then it's 304 :D