Screen-Time Number Detective

A. 75 minutes

Adding 25 and 35 gives 60, then adding 15 gives 75 minutes. The answer totals the three supplied sessions only and does not classify their purpose or value from duration alone.

Try next: Show the three addends beside the total.

B. 12 minutes

Subtracting the planned 28 from the recorded 40 gives 12 minutes. This identifies the numerical difference, while the reason for the longer session would require information not supplied by these two durations alone.

Try next: Keep planned and recorded values visible together.

C. 48 minutes

The second day loses the transferred 12 minutes, leaving 48. The first day becomes 72, and together they still total 120, so the example changes distribution rather than the combined planned duration.

Try next: Check that both revised days still sum to 120.

A. Three hours thirty minutes

Fifteen multiplied by fourteen gives 210 minutes. Three hours account for 180 minutes, leaving 30, so the estimate is three hours and thirty minutes over the stated fourteen-day period in this exercise.

Try next: Write the daily amount and period beside the estimate.

B. 15 minutes

One quarter of 60 minutes is 15 minutes. Multiplying 0.25 by 60 confirms the conversion, while reading the digits as 25 minutes would confuse decimal hours with a clock-style minutes label in this example.

Try next: Write the conversion rule before the answer.

C. 60 percent

Thirty divided by fifty equals 0.6, or 60 percent. The fraction uses the category duration as numerator and the total as denominator, so it describes this record's composition rather than a general recommendation.

Try next: Keep the category label attached to the percentage.

A. Both total 70 minutes

Seven times ten and two times thirty-five both equal 70 minutes. The matching total does not make the patterns identical, since the number and length of sessions differ in the two supplied records.

Try next: Report the shared total and different session patterns.

B. 10 minutes

The ordered list's third value is ten, so its median is ten minutes. The mean would be twenty, but that is a different calculation from the specifically defined middle-value measure requested in this exercise.

Try next: Circle the middle entry in the ordered list.

C. 40 minutes

The covered interval runs continuously from 1:00 through 1:40, totaling 40 minutes. Adding both session lengths would count the ten-minute overlap twice, which the question explicitly instructs the reader not to do here.

Try next: Mark the shared ten-minute interval on a timeline.

A. 18 minutes

The three known entries total 54 minutes, divided by three gives 18. The fourth day is excluded because its value is unknown, so the result must be labeled as a mean of recorded days only.

Try next: State the number of known days beside the mean.

B. 35 measured minutes; elapsed total unknown

The measured segments sum to 35 minutes. Because the pause length is missing, the full elapsed period cannot be calculated, and treating it as exactly 35 would silently assume a zero-length pause without evidence.

Try next: Keep measured activity and total elapsed time separate.

C. 30 percent

The difference is 24 minutes, and 24 divided by the original 80 equals 0.3. That is a 30 percent planned reduction, with actual recorded behavior remaining a separate question not answered by the plan.

Try next: Label the percentage as a planned change.

A. Disclose that the category definitions differ

The earlier combined category does not identify leisure separately. Disclosing the definition change preserves this limitation, whereas a direct comparison or invented split would imply comparable measurements that the available records do not actually provide.

Try next: Keep the earlier combined category labeled as such.

B. Nine minutes per day

Twenty-seven divided by three equals nine minutes. Three equal subtractions of nine rebuild the original 27-minute amount, so checking their sum confirms that the fictional redistribution balances across the stated three days.

Try next: Verify that all three subtractions total 27.

C. One minute thirty seconds

Ninety seconds contains one group of sixty and thirty remaining seconds. That gives one minute thirty seconds, preserving the exact duration rather than using a decimal-looking or rounded label that changes its meaning here.

Try next: Write the remainder after removing sixty seconds.

A. 25 minutes

Subtracting 175 from 200 gives a 25-minute difference between plan and record. The numbers do not describe how other time was used, so the answer should remain a duration comparison rather than a benefit claim.

Try next: State the difference without inventing a replacement activity.

B. Subtract one duplicated 16-minute entry

One copy represents the distinct session and the other is a confirmed duplicate. Removing only the extra entry corrects the inflated sum without erasing the actual recorded session or increasing the duplication in the data.

Try next: Mark the removed copy as a duplicate import.

C. Stop the defined task at form submission

Submitting the specific form is the stated outcome. Using it as the endpoint keeps the session aligned with its purpose, while the other choices expand or leave undefined what completion would mean for this planned task.

Try next: Write the submission endpoint before starting.

A. 110 minutes

Five weekday entries of 22 minutes total 110. The weekend entries are excluded because the question specifically asks for weekdays, illustrating why the requested scope should be checked before calculating a combined total from a table.

Try next: Label the result Weekdays only.

B. 63 minutes

Subtracting the recorded 37 from the combined 100 leaves 63 minutes. This is a remainder within the fictional plan, not a record of second-day behavior or a recommendation about what anyone should do with it.

Try next: Keep the remainder labeled as planned availability.

C. No; the records need a matching context

Equal values do not establish that the records describe the same session or period. A matching context is needed before connecting the measured use to that plan, so the numeral alone cannot prove adherence here.

Try next: Check dates and record identity before linking the values.

A. 15 minutes

The largest entry is 29 and the smallest is 14, so the range is 15 minutes. This measure describes the spread between extremes, while the sum and mean answer different questions about the same four values.

Try next: Mark the largest and smallest entries first.

B. Count one break for the session

The definition counts uninterrupted sessions, not notification events. A start and end belong to one session here, so treating both as separate breaks would change the unit being counted and inflate the summary unnecessarily.

Try next: Keep event counts separate from session counts.

C. 73 hours

Twelve times 365 gives 4,380 minutes, divided by 60 gives 73 hours. The calculation is valid under the stated constant-daily assumption, which should remain visible rather than being presented as an observed future result.

Try next: Label the figure as a projection with its assumption.

A. Show each total with its period

Different observation lengths affect total duration. Showing the periods preserves that context before comparison, whereas assuming equal weeks or hiding dates would make the larger total appear directly comparable without the needed time-window information.

Try next: Record the start and end of each period.

B. Choose the available paper puzzle

The paper puzzle is available in the stated setting, unlike the missing tool. Choosing it matches the practical constraint, while pretending resources exist or adding a much longer task would ignore the actual break conditions.

Try next: Keep alternatives tied to available time and materials.

C. Shorter sessions were recorded after the change; cause is uncertain.

The record supports an observed sequence but not a uniquely established cause. Reporting that sequence with uncertainty preserves useful information, while claiming sole causation or denying the observation would go beyond or against the supplied evidence.

Try next: Include other known changes when reviewing the experiment.