Answer:
Combining statement 1 and statement 2 is sufficient
Explanation:
There are 3 items purchased
Most expensive item=20% discount
The other two items=10% discount each
Statement 1: The average (arithmetic mean) of the regular prices of the 3 items was $30.
Assume:
The 3 items cost: $40, $30 and $20 respectively,
Total discount =20% of $40 + 10% of $30 + 10% of $20
=$8 + $3 + $2
= $13
Assume
The 3 items cost: $50, $30 and $10 respectively,
Total discount = 20% of $50 +10% of $30 + 10% of $10
=$10 + $3 + $1
= $14
Therefore, statement 1 is INSUFFICIENT
Statement 2: The most expensive item was $50
The discount for the most expensive item at $50 = 20% of $50
= 0.2*$50
=$10
But we don't know the price of the other 2 items, so we can't determine the discounts.
Therefore, Statement 2 is also INSUFFICIENT
Combining statement 1 and 2
1) The average (arithmetic mean) of the regular prices of the 3 items was $30.
So, the SUM of the 3 items = $90
2) The most expensive item is $50
So the OTHER 2 items sum up to $40
$50 item gets 20% discount and the other two items ($40) each get 10% discount
The discount = 20% of $50 + 10% of $40
=0.20*50 + 0.1*40
=$10 + $4
=$14
Combining the two statements is sufficient