Answer:
150 boys were enrolled in 2012
Step-by-step explanation:
Let the number of boys enrolled in 2012 be x
Let the number of girls enrolled in 2012 be x + 200
Ratio of boys to girls in 2012 enrollment = 3/7
Now;
3/7 = x/x + 200
7x = 3(x + 200)
7x = 3x + 600
7x - 3x = 600
4x = 600
x = 600/4
x = 150 boys
Hence, 150 boys were enrolled in 2012
You would need to make them eliminate so I would multiply the entire first one by 2.5 to make the X's cancel out. So you would end up with -5X+7.5Y=17.5. The X's would cancel and you would be left with 15.5Y=15.5. So Y=1. Then replace Y into one of the equations. I'm going to use the top again. -2X+3(1)=7. Subtract 3 from both sides to get -2x=4. Divide both sides by negative 2 to get X=-2. So the solution would be (-2,1)
The number of time it would take Todd to paint the room alone is 15 hours.
- Let the Todd's time be t.
<u>Given the following data:</u>
To calculate the number of time it would take Todd to paint the room alone:
How to solve a word problem:
In order to solve this exercise, we would first of all calculate their individual rate and combined rate respectively. Finally, we would add their individual rates together and equate it to the combined rate.
<u>For </u><u>Sue</u><u>:</u>

<u>For </u><u>Jeff</u><u>:</u>

<u>For </u><u>Todd</u><u>:</u>

<u>Combined rate:</u>

Adding the individual rates, we have:

Multiplying all through by 120t, we have:

t = 15 hours.
Read more on word problems here: brainly.com/question/13170908
Answer:
128
Step-by-step explanation:
Billy has 55 stamps and his brother Tommy has 73. Add 73 and 55 together. 55+73=128
Answer:
if exterior angle is 10 degrees, then interior angle is 180 -10 = 170 deg.
Each trinaglke inside the polygon will be isosceles with two angles of 170/2 - 85 degrees each.
So, angle at centre = 180 -170 = 10 deg.
Ttal angle at centre = 360 deg.
No of sides = 360 /10 = 36 sided polygon.
b) Sum of interior angles is given by (2N-4) Right angles
So: 9900 = (2N-4)x90 = 180N - 360
180N = 9900 +360 = 10260
N = number of sides = 10260 / 180 = 57 sides