5X10=50 sq ft area
Around the 3 sides= 5+10+5=20
Answer: 36 seconds
Step-by-step explanation:
A: 9, 18, 27, 36
B: 12, 24, 36
Answer:D
Step-by-step explanation:
This is combination.
If 4 books selected out of eight book in the shelf:
(4 combination 8)= 70
For hardback selection:
Then selection of 4 books out of the hardback, it means there is no paperbach will be:
(4 combination 6)= 15
So , if at least one paperback selected will be : 70-15
That is 55