A keyboard costs £28 before the sale. work out the total cost of the computer and the keyboard.
2 answers:
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The area of the considered composite figure is given by: Option: 6π + 16 cm²
<h3>How to calculate the surface area of a composite figure?</h3>Surface area are derived for some standard shapes like circle, triangle, parallelogram, rectangle, trapezoid, etc.
When some shape comes which isn't standard figure, then we find its area by slicing it (virtually, like by drawing lines) in standard shapes. Then we calculate those composing shapes' area and sum them all.
Thus, we have:
That ∑ sign shows "sum"
For this case, the missing image is attached below.
As visible, the area of the figure = Sum of area of those 3 semi circles + Area of that square(its square because it has 4 equal sides in which adjacent sides are perpendicular) in between.
The side of the square is of 2+2=4 cm( as half of its side is 2 cm), thus, Area of that square = 4² = 16 cm²
All those 3 semicircles has radius = 2 cm
Since radius is same, so area of those 3 semicircle is same =
Thus, we get:
Area of the composite figure =
Learn more about area of a composite figure here:
The underlying arithmetic progression is
-15, 0, 15, 30, ...
starting with and with a common difference of
between terms. Recursively, this sequence is given by
So we have
and so on, so that the explicit rule for the sequence is
for .
The series consists of 15 terms, since
So we have
and the answer would be B.