Let's pick one person at random and call it the 'first'.
That person shakes hands with 29 other classmates.
Take another person different from the first, we'll call him the 'second'. Since he has already shaken hands with the first, he shakes hands with 28 other classmates.
The 'third' person will likewise shake hands with 27 other classmates, and so on.
Hence, the total number of handshakes is 29+28+27+...+2+1 = 29*30/2=435 handshakes
Answer:
<em>1+√3</em>
Step-by-step explanation:
Area of the triangle = 1/2 * base * height
Area of the triangle = 1/2 * AC * BD
We need to get AC
AC = AD+DC
Get base AD using SOH CAH TOA
tan 45 = 4/AD
AD = 4/tan45
AD = 4/1
AD = 4
Get DC
tan 30 = 4/DC
DC = 4/tan 30
DC = 4/(1/√3)
DC = 4√3
AC = 4 + 4√3
AC = 4(1+√3)
Get the Area of the triangle
<em>Area = 1/2 * 4 * 4(1+√3)</em>
<em>Area of the triangle = 1+√3</em>
3/4 of 4/5 = 3/4 x 4/5 = 12/20 = 3/5 of a mile (= 1056 yards)
Answer:
20%
Step-by-step explanation:
Use the percent change formula: difference = % * original cost
12 - 10 = 2
The difference is 2 and the original cost is 10. Now, we have the equation
2 = % * 10. We don’t know the percentage right? So now we have to find the percentage. To do this, you will have to do 2 divided by 10, which is 0.20. Lastly, we have to turn 0.20 into a percentage by multiplying it by 100, leaving you with 20%. So therefore, 20% is the percent increase. Hope this helps!
