400/1600 =25%
Explanation:
Total=1,200+400=1,600
The numbers DO differ by 10 if they are
- 1 and 11
- 2 and 12
- 3 and 13
- 4 and 14
- 5 and 15
Each outcome technically has two ways of occurring, but since we're taking two marbles at a time, that would be the same as saying, for instance, that drawing 1 and 11 is the same as drawing 11 and 1. We only count such an event once.
So the answer is (a) 5.
220
from 218 the 1 is in the tens column. this is the figure that needs to be rounded.
using the following rule
If the digit after the 1 is ≥ 5 then round 1 up to 2
If the digit after the 1 is < 5 then the 1 remains as 1
here the digit after the 1 is 8 so the 1 in the ten's column becomes 2 and the 8 is replaced by 0
218 ≈ 220 ( to the nearest ten )
