answers:
2 11/12
12/35
6
2
2007-02-12 04:01:03 · 4 answers · asked by jj c 1 in Science & Mathematics ➔ Mathematics
5*7/(5+7) = 35/12 = 2 11/12 hours
This is product over sum.
It is same as reciprocal of sum of reciprocals which is:
1/(1/5 +1/7)= 1/(12/35) = 35/12 = 2 11/12.
Yet another way to do it is smaller into larger, add 1, and divide this into larger:
7/5 +1 = 12/5 and 7 /(12/5) = 35/12 = 2 11/12.
2007-02-12 04:08:44 · answer #1 · answered by ironduke8159 7 · 0⤊ 0⤋
We need to add their speeds. So 1/5 + 1/7 = 12/35 now reverse of that gives the time in hours.
35/12 = 2 hrs 55 minutes so first answer is correct.
2007-02-12 12:12:10 · answer #2 · answered by Swamy 7 · 0⤊ 0⤋
This is my guess:
Answer: 6
Equation: 7+5 divided by 2
2007-02-12 12:09:48 · answer #3 · answered by anonymous lucy 3 · 0⤊ 2⤋
a
2007-02-12 12:51:37 · answer #4 · answered by Virgilio C 2 · 0⤊ 0⤋