Answer: x=8
Step-by-step explanation:
This is a simple cross multiplication problem:
12/15=x/10
=> 15x=120
=> x=8
There is your answer.
Have a nice day! :)
We need to call for x minute
+ Phone Company A charges a monthly fee of $42.50, and $0.02 for each minute talk time. So we have to spend: <span>$42.50+ $0.02x
+ </span>Phone company B charges a monthly fee of $25.00, and $0.09 for each minute of talk time. So we have to spend: <span>$25.00+ $0.09x
We solve for x: </span>$42.50+ $0.02x> <span>$25.00+ $0.09x
or </span>$42.50- $25.00 > $0.09x- <span>$0.02x
and we have $0.07x<$27.50
or x< 27.50:0.07 and x< 393.86
The answer is:
If we have to call much time, at least 394 minutes, we should choose A
If not, choose B</span>
100 cm = 1m
To find 60 000cm, multiply by 600 :
60 000 cm = 600m
To convert from m to km, divide by 1000 :
600m ÷ 1000 = 0.6km
Well I don't know.
Let's think about it:
-- There are 6 possibilities for each role.
So 36 possibilities for 2 rolls.
Doesn't take us anywhere.
New direction:
-- If the first roll is odd, then you need another odd on the second one.
-- If the first roll is even, then you need another even on the second one.
This may be the key, right here !
-- The die has 3 odds and 3 evens.
-- Probability of an odd followed by another odd = (1/2) x (1/2) = 1/4
-- Probability of an even followed by another even = (1/2) x (1/2) = 1/4
I'm sure this is it. I'm a little shaky on how to combine those 2 probs.
Ah hah !
Try this:
Probability of either 1 sequence or the other one is (1/4) + (1/4) = 1/2 .
That means ... Regardless of what the first roll is, the probability of
the second roll matching it in oddness or evenness is 1/2 .
So the probability of 2 rolls that sum to an even number is 1/2 = 50% .
Is this reasonable, or sleazy ?
