-5x-3=-23
Add 3 to both sides
-5x=-20
Divide both sides by -5
x=4
Final answer: x=4
Check:
-5(4)-3
-20-3
-23
-23=-23
True
Answer:
Katie is 6 years old and Thomas is 3 years old
Step-by-step explanation:
Given that we should let K and T be the current ages of two siblings, Katie and Thomas.
If Katie is currently twice the age of Thomas then,
K = 2T
and in 6 years, Katie will be 4 times Thomas's current age then
K + 6 = 4T
Solving both equations simultaneously by substituting the value of K given in the first equation into the second
2T + 6 = 4T
Collect like terms
6 = 4T - 2T
6 = 2T
Divide both sides by 2
T = 3
Recall that K = 2T
K = 2 * 3
= 6
Hence Katie is 6 years old while Thomas is 3 years old
Answer:
P(X < 4) = 0.5
Step-by-step explanation:
For each question, there are only two possible outcomes. Either it is answered correctly, or it is not. The probability of a question being answered correctly is independent of any other question. This means that we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
In which 
is the number of different combinations of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
In this question, we have that:
Find the probability that the number of correct answers is fewer than 4:
This is
So
P(X < 4) = 0.5
A circle would be the answer
