Answer:
Step-by-step explanation:
If it is asking for 1.5 standard deviations above the mean, it is 30 +1.5(6)=39
Let x be the first digit.
Let y be the second digit.
Let z be the third digit.
x+y+z=18
y= (-2)(-4)
y= 8
x= 3^2
x= 9
Therefore z=1.
The number is
= 100x+10y+z
= 100(9)+10(8)+(1)
= 981
Answer:
11 speakers
Step-by-step explanation:
2 3/4 ÷ 1/4
11/4 ÷ 1/4
11/4 x 4/1 = 44/4 = 11
Answer:
The area of the trapezoid is 57.5 square inches
Step-by-step explanation:
we know that
The trapezoid QRST can be divided into a rectangle QRDT and an isosceles right triangle RSD
see the attached figure to better understand the problem
step 1
The area of rectangle is given by the formula
we have
----> altitude
substitute
step 2
Find the area of the isosceles right triangle
The area of triangle is given by the formula
we have
---> because is an isosceles triangle
substitute
step 3
Adds the areas
The area formula for rectangles is lxw. To solve, I would divide the figure up into 3 rectangles- top,middle and bottom, then find the areas and add them together.
Top: 4x13=52 cm^2
Middle: 5x8=40 cm^2
Bottom: 21x10=210 cm^2
(5 is the width of the middle piece. You get it from subtracting. 21-8-8=5. 13 is the width of the top piece. 5+8=13)
52+40+210
=302 cm^2
So your answer is 302 square centimetres.
