You could use a calculator or carry out long division. But far quicker than either is:
4950 = 5000 - 50 = 50*100 - 50
So
4950 = [50*100 - 50]/25 = 50*100/25 - 50/25 = (50/25)*100 - 50/25 = 2*100 - 2 = 200 - 2 = 198
That looks quite long but that is because each step is given. You should be able to skip many of the steps.
2475
0.48
25
2.5 divide by 67.5 = 0.037037037037037035
The answer is 112. To calculate: 25/100*448 (25 divided by 100 multiplied by 448)
25% is a quarter, so 160% divided by 4 = 40%
0.0833
25
3600/4950 simplified is 8/11.
3600/4950 = 8/11
The LCM is 4950.
0.025