Answer:
450cm3 or 450 cube cm.
Step-by-step explanation:
Formula = Length x Width x Height
So,
5 x 7.5 x 12 = 450cm3
5*30 = 150
9*30 = 270
Since the ratio is 5:9 you have to multiply both numbers in the ratio by the same constant.
I just started multiplying by 10, then 20, then 30 until I got numbers that had a difference of 120.
There are 150 boys.
Setting up an equation
5x + 120 = 9x
Solve for x and then multiply the ratio by the x to get the same result.
Answer:
C
Step-by-step explanation:
Ax+by= C
Ax -Ax +By = C -Ax
By = C-Ax
By/B = C-Ax/B
y= C-Ax/B
Answer:
The area of the triangle is 351cm^2.
Step-by-step explanation:
To find the area of a triangle, the formula is (1/2) x base x height. In this case, the height would be a line that cuts straight through the center of the triangle. However, this height is not given to us. We can still find it through Pythagoras' Theorem though.
Let A be the tip of the triangle, and B and C be the points on either side of the triangle. Assuming an imaginary line that cuts the triangle in a symmetrical half, let T be the point at the end of the line, directly below point A.
Using Pythagoras' Theorem,
AB^2 = AT^2 + TB^2
AT^2 = AB^2 - TB^2
AT^2 = 30^2 - (26/2)^2
AT^2 = 30^2 - 13^2
AT =

AT = 27.0370116692
So the length of AT is our height. We can now find the area of the triangle.
Area of triangle = (1/2) x 26cm x AT
Area of triangle = 351.4811516996
Area of triangle = 351cm^2 (To 3s.f.)