BeginnerMath Functions
Total a month of sales with SUM
Add up a column of daily sales figures to get the monthly total.
SUM
3 min10 points
Excel for operations
Operations spreadsheets are early-warning systems: they exist to flag the thing that is about to go wrong.
What the job actually asks for
Stock against reorder points, on-time delivery rates, throughput by site and shift. The value is not in the arithmetic but in the flagging — a sheet that surfaces the twelve rows needing attention out of four thousand that do not.
The recurring tasks
- Track stock levels against reorder points
- Calculate on-time delivery rates
- Flag items below safety stock
- Summarise throughput by site and shift
Where people get caught
Boundary conditions. A rule that says 'more than 30 days' implemented with >= flags everything a day early, and because the output looks reasonable the error can run for months.
What interviews test
Conditional counting across several criteria, flagging exceptions with IF, and explaining how you would check a threshold rule is behaving at its edges.
Practice built from operations work
10 exercises using the situations above, ordered from most approachable to hardest.
- BeginnerStatistical Functions
Count how many orders shipped with COUNT
Use COUNT to find how many rows contain a numeric value.
COUNT
4 min10 points - BeginnerText Functions
Check code length with LEN
Use LEN to validate that product codes are the right length.
LEN
3 min10 points - BeginnerStatistical Functions
Count orders above a threshold with COUNTIF
Count how many rows meet a numeric condition.
COUNTIF
5 min15 points - BeginnerText Functions
Build a mailing address with TEXTJOIN
Combine separate address fields into one line, skipping blanks.
TEXTJOIN
6 min15 points - IntermediateStatistical Functions
Count orders meeting two conditions
Count rows that satisfy several criteria at once.
COUNTIFS
8 min25 points - IntermediateLogical Functions
Approve orders with AND
Require two conditions to be true at once.
IF · AND
8 min25 points - IntermediateText Functions
Pull the year out of an order code with MID
Extract characters from the middle of a text value.
MID
7 min25 points - IntermediateData Cleaning
Standardise messy codes with TRIM and UPPER
Clean inconsistent spacing and casing so values can be matched.
7 min25 points - IntermediateDate & Time
Calculate invoice age with TODAY
Work out how many days old each invoice is.
TODAY
8 min25 points