A) Olaf has 250 files, which represent 100%. 12% of that are photos which number is unknown (x).
250 files - 100%
x photos - 12%
So, the proportion should look like:
250 files : 100% = x : 12%
B) After crossing the products:
x = 250 files * 12% : 100%
x = 30 photos
I'm pretty sure you can only do it by calculator
Press the SIN button, open parentheses, 180, close parentheses,
And hit enter
Hope this helps :)
1: -4
2: -2 3/4
3: 1/10
4: 2 1/5
5/12 converted. decimal would be .416666667