Difficulty level: 600
To find the time duration of Wanda's call,
Total charge for the call = $6.5, we neither know the number of minutes nor call charges. Insufficient.
Wanda was charged $0.50 more for the first minute of the telephone call than for each minute after the first.
x+0.5 for first minute,
for second minute x, & so on,
for the whole call total charges would be nx+0.5 (n = number of minutes)
or nx+0.5 = 6.5
or nx = 6 (1*6 or 6*1 or 2*3 or 3*2)
thus, (n,x) = (1,6) or (6,1) or ....
which means, for 1 min $6 can be charged.
or for 6 mins $1 can be charged. Insufficient.
Answer is (E),
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