I need help on four questions. Here's a screen shot link to them. (I don't know how to properly write it as a fraction)
http://vvcap.net/db/MLEpryNKi9JQZsqN9wdo…
http://vvcap.net/db/MLEpryNKi9JQZsqN9wdo…
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Well, instead of actually writing these as fractions, you need to solve for the missing variable. The process to complete this is called cross multiplication.
Here's an image of how to do the cross multiplication process. It's pretty simple once you get the hang of it: http://www.mathsisfun.com/algebra/images…
1.) (16/17) = (x / 40)
17x = 16*40
17x = 640
x = 640 / 17
x ≈ 37.7
2.) (4a / 9) = (100 / 45)
45*4a = 9*100
180a = 900
a = 900/180
a = 5
3.) (3 / 0.8) = (12 / b)
3b = 12*0.8
3b = 9.6
b = 9.6 / 3
b = 3.2
4.) (3 / 4) = (21 / 2 + d)
3*(2 + d) = 4*21
6 + 3d = 84
3d = 82
d = 82/3
d ≈ 27.3
Hope this helps! :-)
Here's an image of how to do the cross multiplication process. It's pretty simple once you get the hang of it: http://www.mathsisfun.com/algebra/images…
1.) (16/17) = (x / 40)
17x = 16*40
17x = 640
x = 640 / 17
x ≈ 37.7
2.) (4a / 9) = (100 / 45)
45*4a = 9*100
180a = 900
a = 900/180
a = 5
3.) (3 / 0.8) = (12 / b)
3b = 12*0.8
3b = 9.6
b = 9.6 / 3
b = 3.2
4.) (3 / 4) = (21 / 2 + d)
3*(2 + d) = 4*21
6 + 3d = 84
3d = 82
d = 82/3
d ≈ 27.3
Hope this helps! :-)