Estimate each of the following using general rule:

(a) 730 + 998 (b) 796 − 314 (c) 12, 904 + 2, 888

(d) 28, 292 − 21, 496

Make ten more such examples of addition, subtraction and estimation of their outcome.

(a) 730 + 998

By rounding off to hundreds, 730 rounds off to 700 and 998 rounds off to 1000.

(b) 796 − 314

By rounding off to hundreds, 796 rounds off to 800 and 314 rounds off to 300.

(c) 12904 + 2822

By rounding off to thousands, 12904 rounds off to 13000 and 2822 rounds off to 3000.

(d) 28,296 − 21,496

By rounding off to nearest thousands, 28296 rounds off to 28000 and 21496 rounds off to 21000.