20 students have each sampled one or more of three kinds of candy bars that a school store sells. If 3 students have sampled all three kinds and 5 have sampled exactly 2 kinds, how many of these students have sampled only one kind?
2007-06-01 19:06:00 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
20-(3+5)=12
2007-06-01 19:11:39 · answer #1 · answered by Oswald F 3 · 1⤊ 0⤋
This is just logic.
If there were 20 students all together:
3 students sampled three kinds.
5 students sampled two kinds.
The rest of the 20 students must have sampled only one kind.
20 - (3 + 5) = 12 students
2007-06-02 02:12:04 · answer #2 · answered by ecolink 7 · 1⤊ 0⤋
No. of children = 20
No. who sampled all 3 = 3
No. who sampled pnly 2 = 5
No. of studets who sampled one = 20 - (3+5)
= 20 -8
= 12
2007-06-02 02:21:51 · answer #3 · answered by M.A.S.H.I 2 · 0⤊ 0⤋
12 students. It's basic arithmetic.
2007-06-02 03:27:35 · answer #4 · answered by whitey-chan 3 · 0⤊ 0⤋