Question

Estimate each of the following using general rule :
Make ten more such examples of addition, subtraction and estimation of their outcome.
$730+998$

Answer 1

Step 1 : Evaluate addition by rounding off to nearest hundreds
Given, $730+998$

Round off to hundreds

$730$ rounds off to $700$

$998$ rounds off to $1000$

Hence, $730+998=700+1000=1700$

Step 2 : Make ten more such examples
Ten more such examples are

$i.330+280=300+300=600$
$ii.3937+5990=4000+6000=10000$
$iii.6392–3772=6000–4000=2000$
$iv.5440–2972=5000–3000=2000$
$v.2175+1206=2000+1000=3000$
$vi.1110–1292=1000–1000=0$
$vii.910+575=900+600=1500$
$viii.6400–4900=6000–5000=1000$
$ix.3731+1300=4000+1000=5000$
$x.6485–4319=6000–4000=2000$