1
00:00:00,080 --> 00:00:04,490
Eight units were purchased at twelve dollars, but only two at eight dollars.

2
00:00:04,490 --> 00:00:08,900
A simple average gives each batch the same weight and says ten dollars.

3
00:00:08,900 --> 00:00:12,632
To answer what one unit cost on average, we will weight

4
00:00:12,632 --> 00:00:15,685
by units and verify ten dollars and eighty cents.

5
00:00:16,285 --> 00:00:20,253
The practice file has batch A with two units at eight

6
00:00:20,253 --> 00:00:24,222
dollars, batch B with eight units at twelve, and batch C

7
00:00:24,222 --> 00:00:26,026
with five units at ten.

8
00:00:26,026 --> 00:00:29,634
Multiply each quantity by its own price before combining anything.

9
00:00:29,634 --> 00:00:32,520
This gives sixteen, ninety-six, and fifty dollars.

10
00:00:33,120 --> 00:00:36,311
AVERAGE of eight, twelve, and ten is ten dollars.

11
00:00:36,311 --> 00:00:40,566
That treats the two-unit batch and eight-unit batch as equally

12
00:00:40,566 --> 00:00:44,111
important, even though they represent different numbers of purchased units.

13
00:00:44,111 --> 00:00:48,011
Ten is a valid average of listed price labels, but not

14
00:00:48,011 --> 00:00:50,139
the actual price paid per unit.

15
00:00:50,739 --> 00:00:55,032
Enter =SUMPRODUCT(B2:B4,C2:C4)/SUM(B2:B4).

16
00:00:55,032 --> 00:01:00,756
SUMPRODUCT multiplies aligned quantities and prices, then adds the three batch costs.

17
00:01:00,756 --> 00:01:03,142
SUM counts fifteen total units.

18
00:01:03,142 --> 00:01:08,389
Dividing one hundred sixty-two dollars by fifteen units gives ten

19
00:01:08,389 --> 00:01:11,251
dollars and eighty cents per unit.

20
00:01:11,851 --> 00:01:16,005
Check the numerator separately: sixteen plus ninety-six plus fifty

21
00:01:16,005 --> 00:01:18,497
equals one hundred sixty-two dollars.

22
00:01:18,497 --> 00:01:23,066
Check the denominator: two plus eight plus five equals fifteen units.

23
00:01:23,066 --> 00:01:27,635
The two independent totals make ten dollars and eighty cents auditable

24
00:01:27,635 --> 00:01:30,127
rather than a mysterious formula output.

25
00:01:30,727 --> 00:01:34,799
A SUMPRODUCT range ending on row five while the other ends

26
00:01:34,799 --> 00:01:37,390
on row four can produce an error.

27
00:01:37,390 --> 00:01:41,833
The denominator must use the same fifteen units represented in the numerator.

28
00:01:41,833 --> 00:01:45,905
If a new batch is added, expand all relevant ranges together

29
00:01:45,905 --> 00:01:49,607
or convert the source to a Table with deliberate references.