S=number of 6 cent stamps
t=number of ten cen stamps
e=number of 8 cent stamps
w=number of 20 cents stamps=2
cost=500 cents
6s+10t+8e+20w=500
w=2 since two 20 cent stamps wer bought
6s+10t+8e+40=500
minsu 40 both sides
6s+10t+8e=460
divide both sides by 2 to simplify
3s+5t+4e+230
also
10 more 6 cent than 10 cent
s=10+t
8 cent stamps is 3 times 10 cent stamps
e=3t
sub
s=10+t
e=3t
3(10+t)+5t+4(3t)+230
30+3t+5t+12t=230
30+20t=230
minus 30
20t=200
divid 20
t=10
sub back
s=10+t
s=10+10
s=20
e=3t
e=3(10)
e=30
20 six cent
30 eight stamp
10 ten cent
2 twenty cent
Answer:
d. 3x + 6 = 26
Step-by-step explanation:
<u>Definitions</u>
- Integer: a whole number that can be positive, negative or zero.
e.g. ..., -3, -2, -1, 0, 1, 2, 3, ... - Even number: an integer that is exactly divisible by two. For example, 2, 4, 6, 8 are all positive even numbers.
- Consecutive: following one after the other in order.
<u>The sum of three consecutive even integers</u>
Let x be the first even integer.
As there is a <u>difference of 2</u> between <u>consecutive even integers</u>, the next even integer after x will be (x + 2).
Therefore, the next even integer after (x + 2) will be (x + 2) + 2 = (x + 4).
So "the sum of three consecutive even integers is twenty-six" is:
x + (x + 2) + (x + 4) = 26
<u>To solve</u>
⇒ x + (x + 2) + (x + 4) = 26
⇒ x + x + 2 + x + 4 = 26
⇒ 3x + 6 = 26
(Please note that there are no three consecutive even integers that sum to 26, so the problem cannot be solved).
Answer:
See below in bold,.
Step-by-step explanation:
There are 30-17 = 13 boys in the class.
a. Prob(First is a boy ) = 13/30 and Prob( second is a boy = 12/29).
As these 2 events are independent:
Prob( 2 boys being picked) = 13/30 * 12/29 = 26/145 or 0.179 to the nearest thousandth.
b. By a similar method to a:
Prob ( 2 girls being picked) = 17/30 * 16/29 = 136/435 = 0.313 to the nearest thousandth.
c. Prob (First student is a boy and second is a girl) = 13/30 * 17/29 = 221/870.
Prob ( first student is a girl and second is a boy) = 17/30 * 13/29 = 221/870
These 2 events are not independent so they are added:
Prob( one of the students is a boy) = 2 (221/870 = 221/435 = 0.508 to the nearest thousandth.
Step-by-step explanation:
Exponential function: f(x)=250(1.03)^x
Simplify both sides of the equation.
f(x)=250⋅1.03x
Evaluate the function.
250⋅1.03x
Probability? I'm guessing it is asking for a written response so I'll try my best.
If the coin landed heads up 16 times then the probability would be 16/40 which can be reduced to 2/5
If the coin landed tails up 24 times you would do the same so 24/40 and then you can reduce that to 3/5
Part a: The experimental probability of it being tails would be 3/5
Part b: The experimental probability of it being heads would be 2/5
hopefully, I understood the question correctly but I believe this is the right answer