ESTIMATION-ADDITION AND SUBTRACTION

ESTIMATION-ADDITION AND SUBTRACTION

FIND THE ACTAUL SUM AND ESTIMATED SUM OF 45 AND 238

• 45 + 238 = 283

• 45 = 50 (NEAREST 10)

• 238 = 240 (NEAREST 10)

• 50 + 240 = 290

• ACTUAL SUM = 283

• ESTIMATED SUM = 290

ESTIMATION

FIND THE ACTUAL SUM AND ESTIMATED SUM OF 106 AND 354.WHAT WILL HAPPEN IF WE ROUND EACH NUMBER TO NEAREST 100 AND FIND THE SUM.

RULES FOR ESTIMATING SUM/DIFFERENCE

There are no rigid rules when you want to estimate the outcomes of numbers. The procedure depends on the degree of accuracy required and how quickly the estimate is needed. The most important thing is, how sensible the guessed answer would be.

Multiple Choice

Estimate the answer:

578 + 720

• 1300

• 1200

• 1290

• 1298

Multiple Choice

Estimate the answer:

906 + 397

• 1300

• 1200

• 1310

• 1303

Multiple Choice

Round to the nearest hundred to estimate 2,252 - 198.

• 2,300 - 200 = 2,100

• 2,000 - 200 = 1,800

• 2,200 - 200 = 2,000

• 2,250 - 200 = 2,050

Multiple Choice

Estimate the difference to the nearest hundred: 573-263

• 300

• 3000

• 310

• 30

Multiple Choice

Which is the best estimate for 49 x 27?

• 1,500

• 150

• 1,000

• 100

Multiple Choice

Using estimation, 36 x 69 is closest to...

• 1800

• 2800

• 2400

• 1200