533,030 in 3 years, simply grab the percentage of the whole amount and double the interest by several years and add up.
74 is a composite number. 74=1*74 or 2*37. Factors of 74: 1,2,37,74. Prime factorization: 74=2*37.
About 68% of the people will score between 85 and 115.
The values of 85 and 115 are exactly 15 points away, or 1 standard deviation, away from the mean.
According to the empirical rule, about 68% of the values in a normal distribution are within 1 standard deviation of the mean.
11/4% = (11/4)/100 = 11/400 = 0.0275;
1/4 = 0.2500;
1/80 = 0.0125;
We observe that 0.0125 < 0.0275 and 0.0114 < 0.0275 and 0.2500 > 0.0275 and 0.12500 > 0.0275;
The answers are c. and d.