Answer is D) 5 mc, 15 t&f
you have two unknown variables, thus you need two equations
definitions:
a = quantity of multiple choice questions
b = quantity of true and false questions
100 points = a*11 points/question + b*3 points/question
20 questions = a +b
using 2nd equation, find equation for 'a':
a = 20 - b
substitute this equation for 'a' into 1st equation:
100 = 11a + 3b
100 = 11(20 - b) + 3b
100 = 220 - 11b + 3b
100 - 220 = -8b
-120 = -8b
-120/-8 = b
15 = b
resolve 2nd equation now knowing value of 'b':
a = 20 - b
a = 20 - 15
a = 5
verify solution is correct by substituting values into first equation
11a + 3b = 100
11(5) + 3(15) = 100
55 + 45 = 100
100 = 100 [OK]
verify solution is correct by substituting values into second equation
a + b = 20
5 + 15 = 20
20 = 20 [OK]
A
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C)
2/4
2 is half of 4
2 are shaded in out of 4
Y=10x+20
y=10×5y+20
y=50y+20
-20=50y-y
-20=49y
y=-20/49
Answer:
25.000
Step-by-step explanation:
With only this information, the answer would be 25000, if there are 100 light bulbs on EACH strand, then we only have to multipy the number of strands by the number of light bulbs. So 250×100=25000