The following line graph shows the sales and cost of goods sold (in rupees) for XYZ Co. over 10 months, from Month 1 to Month 10. What were the average sales and average cost of goods sold, in rupees, for XYZ Co. over the ten months?
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Add the ten sales figures and divide by 10 for the average sales, then do the same for cost, and match the pair against the options.
A faster check than adding up all twenty numbers is to use the fact that average profit equals average sales minus average cost, and to test each option's implied profit against that.
Find the average monthly profit first: the nine positive profits and one loss from the graph are $400, 125, 375, 275, 125, 25, 275, 100, 100$, and $-50$. Adding these gives $1750$, so the average monthly profit is $1750/10 = 175$.
Option (1819, 1651): the implied profit is $1819-1651=168$, close to the target of $175$.
Option (1919, 1751): the implied profit is $1919-1751=168$ as well, so this option cannot be ruled out on profit alone.
Option (1969, 1762): the implied profit is $1969-1762=207$, noticeably higher than $175$.
Since two options give almost the same implied profit, profit alone cannot separate them, so the sales figure itself must settle it. Looking at the ten sales values (2200, 1750, 1625, 2250, 1700, 1825, 2100, 1450, 1700, 1650), only three months cross 2000, so an average sales figure as high as 1919 is not supported by the data, while 1819 sits comfortably in the middle of the ten values.
Let's summarize:
Average profit works out to $175$, which narrows the choice to the options whose sales minus cost is close to $175$.
Checking the sales values directly then rules out the option with the inflated average of $1919$.
So the average sales and cost were about 1825 and 1650, matching (1819, 1651) most closely.
