When faced with an unknown variable in a maths problem, it is advised to find the subject formula and then use it to solve the equation to find the answer.
<h3>What is an Unknown Variable?</h3>
This refers to the type of variable in a given equation that has to be solved for because its properties or value is not known.
Hence, we can see that when faced with an unknown variable in a given math problem, it is better to find the subject formula, then input the value of this into an equation, to find the value of the variable.
Read more about unknown variables here:
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Answer:
85%
Step-by-step explanation:
If she got 3 wrong then it means she got 20-3 right, so she got 17 questions right.
From there we get the fraction: 17/20
To make the a percentage we times both the top and bottom by 5 (because 20 x 5 = 100)
By doing that we get 17x5/20x5
= 85/100
That is equal to 85%
Step-by-step explanation:
the probability of A working is 60% or 0.6, so the probability it does not work is 40% or 0.4.
the probability of B working is 90% or 0.9, so the probability it does not work is 10% or 0.1.
plan 1
it is the probabilty that either A works, or (if it is not working) B works.
0.6 + 0.4×0.9 = 0.6 + 0.36 = 0.96
plan 2
either B works, or (if it is not working) A works
0.9 + 0.1×0.6 = 0.9 + 0.06 = 0.96
both plans have the same success probability.
C.Quadrilateral is the answer for the following because rhombus, trapezoid, isosceles trapezoid have parallel sides.
Answer:
C (3x4) + (5x2) + 20
Step-by-step explanation:
3 things that cost 4 dollars. 5 things that cost 2 dollars and one that cost 20.