Probably the most effective method researchers use to prevent sampling bias is through simple random sampling where samples are selected strictly by chance.
Answer:
B.
Step-by-step explanation:
x=42
x/6+21=28
28-21=x/6
7=x/6
x=7*6
LCM = 5 × 3 × 3 × 7 × 2 × 2 × 5
LCM = 6300
<u>Hence, the LCM of 315 , 420 , 525 is 6300</u>
108 months old.
Year = 12 months
9 Years = 9 x 12 months
9 years = 108 months.
