9514 1404 393
Answer:
Step-by-step explanation:
The total number of students (32) corresponds to the total number of ratio units (3+5 = 8), so each ratio unit represents 32/8 = 4 students.
The 3 ratio units representing boys will stand for 3×4 = 12 boys.
The 5 ratio units representing girls will stand for 5×4 = 20 girls.
There are 12 boys and 20 girls in Janice's classroom.
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<em>Additional comment</em>
I find the above solution to be the easiest.
You can also write a system of equations. Let b and g represent the numbers of boys and girls, respectively.
b/g = 3/5
b +g = 32
Multiplying the first equation by g gives an expression for b that can be substituted into the second equation:
b = (3/5)g
(3/5)g +g = 32
8/5g = 32 . . . . . . . . . . . . . . . . . collect terms
g = (5/8)(32) = 5·4 = 20 . . . . . . multiply by 5/8
b = (3/5)(20) = 3·4 = 12 . . . . . . . find b using the value of g
C= 2
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Answer:
1. 
2. 
Step-by-step explanation:
Given
Variation: inverse Proportion
y = 7, x = 9
Required
- Write an equation connecting y and x
- Find y when x = 21
Given that thee variation is inversely proportional;
This implies that

Convert variation to equation
----------- Equation 1
Where k is the constant of variation
Substitute 7 for y and 9 for x in equation 1

Multiply both sides by 9


Substitute 63 for k in equation 1

Multiply both sides by x


Hence, the equation connecting x and y is 
Solving for when x = 21
Substitute 21 for x in the above equation

Divide both sides by 21


Answer:
110
Step-by-step explanation:
Answer:
b = 87°
Step-by-step explanation:
In order to answer this question, we need to utilise an important angle fact which is <em>angles in a quadrilateral add up to 360° </em>
Using the information we can set up an equation to find the value of b
→ Form equation
63 + 140 + 70 + b = 360
→ Simplify
273 + b = 360
→ Minus 273 from both sides isolate b
b = 87°