The Circular Reference and the Scholarship Email
Priya is the treasurer of her school's Eco Club in Tiruchirappalli. She records the club's monthly expenses in a spreadsheet called eco_expenses.xlsm, which the previous treasurer saved on the shared Desktop of the computer lab. This month the club collected ₹4,500 from a paper drive and spent money on sacks, gloves and transport across ten rows, B2 to B11. Priya types =SUM(B2:B11) into cell B11 to get the total, and the cell immediately shows 0 with a warning about a circular reference. She has also shared the file's password, eco2024, with two friends so they can help. On Thursday an email arrives from '[email protected]' telling her to 'verify your bank details within 24 hours or lose the ₹5,000 scholarship', with a link. The lab attendant clears the Desktop every Friday at 4 p.m. to free space.
1. Diagnose why the total shows 0, and state the corrected approach with the reasoning behind it.
Read the worked answer
The formula is correct; its location is not. Priya typed =SUM(B2:B11) into B11, so the total is asked to add a range that contains the total. That is a circular reference: the cell depends on itself. The spreadsheet cannot resolve it, shows 0, and if iterative calculation is switched on it may silently return a wrong figure - more dangerous than an error, because nobody notices.
Correct approach: put the total outside the summed range, for example =SUM(B2:B11) in B12 (or D2) with the label 'Total'. Then check the range: if a new expense row 12 is added later, the total must be widened to B2:B12, or the data converted to a table so the range expands automatically. The general rule is that a SUM cell must never sit inside the range being summed.
2. Judge whether the email is genuine or phishing, list the indicators, and state the correct response.
Read the worked answer
It is phishing. Indicators: extreme urgency ('within 24 hours or lose it'), a generic greeting with no name, a sender domain (edu-grants.info) that is not the official scholarship portal, a request to verify bank details - a genuine scholarship body already holds payment details or asks through its own portal - and a scholarship Priya never applied for. Hovering over the link would almost certainly reveal a different destination.
Correct response: do not click, do not reply, and enter nothing. Report it to the lab in-charge or the school's ICT coordinator with the message intact, so other students can be warned. If she is unsure whether the scheme exists, she should open a new tab and type the official portal address herself rather than following the link. Reporting matters more than deleting: one report protects the whole class.
3. Recommend a backup and password practice for the club file, and explain the specific risk in the current arrangement.
Read the worked answer
Two problems combine here. The file sits on a shared Desktop that is wiped every Friday at 4 p.m., and the password eco2024 is weak (a dictionary word plus a year) and shared with two friends, so no edit can be traced to a person.
Backup: save the workbook in the school's cloud drive with version history, and keep a weekly copy on a pen drive held by the club adviser - three copies, two media, one off-site. Keep a short log of who edited what, and never leave the only copy on a Desktop that a cleaner schedule touches.
Password: a passphrase of three unrelated words plus a symbol, used only for this file, known to the treasurer and the adviser, and reset when the role changes. Add two-step verification if the cloud account offers it, and never reuse a school password on a personal account.