The table below shows the drop-out rates, in percentage, at the Primary level (Classes I-V), the Elementary level (Classes I-VIII), and the Secondary level (Classes I-X) in India, separately for boys, girls, and the total, for the years 1996-97 to 2004-05. Gender bias is defined as the disproportion between the drop-out rate of boys and the drop-out rate of girls, at a given level.
Suppose the total number of students was 1000 in 1996-97, and this number increased by 1000 every year up to 2004-05, so 1996-97 had 1000 students, 1997-98 had 2000, and so on up to 2004-05 with 9000. What was the approximate total number of drop-outs from primary classes, added up over 1996-97 to 2004-05?
Show Hint
Multiply each year's number of entering students, 1000, 2000, and so on up to 9000, by that year's primary total drop-out rate, then add up all nine years.
A quick way to sanity-check this total without carrying decimals through nine multiplications is to round the drop-out rates to the nearest whole percent, keep the student counts exact, and add.
Round each year's primary total drop-out rate: 40.2 to 40, 39.2 to 39, 41.5 to 42, 40.3 to 40, 40.7 to 41, 39.0 to 39, 34.8 to 35, 31.5 to 32, and 29.0 to 29 percent.
Multiply each rounded rate by that year's student count: $1000(0.40)=400$, $2000(0.39)=780$, $3000(0.42)=1260$, $4000(0.40)=1600$, $5000(0.41)=2050$, $6000(0.39)=2340$, $7000(0.35)=2450$, $8000(0.32)=2560$, $9000(0.29)=2610$.
Add these nine rounded figures: $400+780+1260+1600+2050+2340+2450+2560+2610=16050$.
This rounded estimate of about $16{,}050$ lands right next to the exact total of $15{,}984$ worked out from the unrounded rates, confirming the same option.
Let's summarize:
Rounding the drop-out rates to whole percentages barely changes the final total.
Both the exact and the rounded calculation point to about 16,000 drop-outs.
So the total number of primary drop-outs across the nine years is closest to 16,000.
