give a rough estimate(by rounding off to nearest hundreds)and also a closer estimate (by rounding off to nearest tens):

(a) 439+334+4,317=

(b) 1,08,734-47,599=

(c) 8325-491=

(d) 4,89,348-48,365=

a) 439+334+4317

rounding off to nearest hundreads-

439=400

334=300

4317=300

= 300 + 400 + 4300 +  = 1000

by rounding off to nearest tens

439= 440 

334=330 

4317= 4320

440 + 330 + 4320 = 5090

b) 108734 - 47599

hundreds

108734 = 108700

47599 = 47600

= 61100

tens

108734= 108730

47599= 47600

= 61130

c)8325-491

hundreads

8325= 8300

491= 500

=7800

tens

8325 = 8330

491 = 500

= 7830

d) 489348 - 48365

hundreads

489348 = 489300

48365 = 48400

= 440900

tens

489348 = 489350

48365  = 48370

= 440980