Question: a snail , climbing a 20 feet high wall , climbs up 4 feet on the first day but slides down 2 feet on the second . it climbs 4 feet on the third day and slides down again 2 feet on the fourth day . if this pattern continues , how many days will it take the snail to reach the top of the wall ?
A) 12
B) 16
C) 17
D) 20
E) 21
Correct answer: C
Grade: 6 | Topic: Expressions and Equations | Difficulty: Hard | Standard: 6.EE.B.6