Answer:
14+9 14×9that is the answer
Since it is a four combination lock or permutation and she wants the last digit to be seven we have_,_,_,7
The first digit: Since we need it to be any number except 7 we have 9 possibilities.For the second digit: We have 8 possibilities since the numbers can't be repeated and we already chose 7 to be the last digit and any other digit to be the first digit.For the third digit: there are 7 possibilities since we already chose three numbers and these cannot be repeated.
We have the following:9*8*7=504
Distribute first, combine the like terms and then add all of the sides up.
Answer:
1140
Step-by-step explanation:
Point A would be zero; Point B, the end of the 1/2-hour time interval, would be 1/2 (representing 1/2 hour). Then Amy needs to subdivide the interval A to B into three equal time intervals and to determine the length of each of these subintervals.
I would begin with 1/2 and divide that by 3:
1
--
2
====
3
--
1
Inverting the fraction in the denom. and multiplying, we get
1 1 1
-- * ---- = -----
2 3 6
So Amy will spend 1/6 th of an hour, or 10 minutes, on each chore.
Note that 3 times 1/6 comes out to 1/2 (hour), which is were we started.
