Let first number = X and 2nd number = Y
Equation 1: 5X + 8Y = -13
Equation 2: 5X + 10Y = -15
Multiply equation 1 by -1 to get: -5X + -8Y = 13
Now add the 2 equations together:
-5X + 5X = 0
-8Y + 10Y = 2Y
13 + -15 = -2
The total of the 2 equations is 2Y = -2
divide both sides by 2 to solve for Y
Y = -2 / 2
Y = -1
Now we know the 2nd number is -1, so replace Y in the 1st equation and solve for X
5X +8(-1) = -13
5x + -8 = -13
Add 8 to both sides:
5x = -5
Divide both sides by 5 to get x
X = -5 / 5
X = -1
Both numbers are -1
To check replace X and Y with -1 and solve:
1st equation: 5(-1) +8(-1) = -5 + -8 = -13 TRUE
2nd equation: 5(-1) +10(-1) = -5 + -10 = -15 TRUE
Both numbers are -1
The probability of selecting a blue marble is <u>3/14</u>. Hence, <u>option D</u> is the right choice.
The probability of any event is the chance of the occurrence of that event. It is given as the ratio of the number of favorable outcomes to the event to the total number of outcomes possible in the experiment.
If we consider an event A, the number of favorable outcomes to event A be n, and the total number of outcomes be S, then the probability of event A is given as:
P(A) = n/S.
Let us take the event of selecting a blue marble from the experiment of selecting a marble randomly from the bag be A.
The number of outcomes favorable to event A (n) = 3 {3 blue marbles}.
The total number of outcomes (S) = 14 {Total number of marbles in the bag = 4 red + 3 blue + 7 green = 14 marbles}.
Therefore, the probability of selecting a blue marble is,
P(A) = n/S = 3/14.
Hence, <u>option D</u> is the right choice.
Learn more about the probability of an event at
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For landing on heads the fraction is 1/2 which is 50%
Answer:
It is Number 1 A
Step-by-step explanation:
