Number of students in senior class is 130
<em><u>Solution:</u></em>
Given that Every student in the senior class is taking history or science
85 of them taking both history and science
106 seniors takes history
109 seniors takes science
To find: number of students in senior class
Let A be the set of the students of the senior class that take history
Let B be the set of students of senior class that they science
The number of students in senior class is given by:
Where,
A = 106 and B = 109 and |A n B| = 85
Thus number of students in senior class is 130
Answer:
The answer is option (D). 4+b=16;b=12 more books
Step-by-step explanation:
Step 1: Derive expression for total number of books to be read
The expression for the total number of books to be read is;
T=a+b.... equation 1
where;
T=total number of books to be read
a=total number of books already read
b=number of books not read
In our case;
T=16 books
a=4 books
b=unknown
replacing;
16=4+b
4+b=16...equation 2
solving;
b=16-4
b=12
You need to read 12 more books to reach your target
Answer: The scale is 5cm/m (5 cm in the drawing are equivalent to 1 meter on the actual pit)
Step-by-step explanation:
When we have an original measure M, and we redraw it with a new scale, where the new measure is m, the scale used is equal to:
scale = m/M.
In this case, we know that:
The pit is 3m, by 5m
and the drawing to scale is 15cm by 25cm
(15cm is the rescaled version of the 3m side, and 25cm is the rescaled version of the 5m side)
Using the equation above, we can find that the scale is:
Scale = 15cm/3m = 5cm/m
and, if we use the other side, we get:
Scale = 25cm/5m = 5cm/m
Both calculations give the same scale, as expected.
Then the scale is 5cm/m, which means that 5 centimeters in the drawing are equivalent to one meter in the real pit.
<h3>✎
Answer:</h3>
Option B is your answer
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<h3>❆❆❆❆❆❆❆❆❆❆❆</h3><h3>hope it helps..</h3><h3>have a great day!!</h3>
