Use knowledge of column addition to solve problems in a range of contexts | Exit Quiz | Oak National Academy

Each of Enzo the elephant’s tusks are 315 cm long. Which would be the most accurate estimate for the length of both of his tusks?

• 500 cm

• 600 cm

• 700 cm

• 800 cm

Answer explanation

315 is close to 300; 300 cm add 300 cm is equal to 600 cm.

Each of Enzo the elephant’s tusks are 315 cm long. What is the total length of both of his tusks? (a)   cm.

Answer explanation

315 + 315 = 630, so both tusks are 630 cm.

Eddie the elephant is 347 cm tall. With his trunk, he can reach an extra 148 cm upwards. How far can he reach altogether? Eddie can reach (a)   cm.

Answer explanation

347 + 148 = 495 so Eddie can reach 495 cm.

Which calculation is the best one to estimate the sum of 459 + 289?

• 400 + 200

• 400 + 300

• 450 + 300

• 500 + 300

Answer explanation

450 + 300 will give the most accurate estimate.

Look carefully at Alex’s column addition. Which of these statements about the sum is true?

• The ones digit is incorrect.

• The tens digit is incorrect.

• The hundreds digit is incorrect.

• The sum is correct.

Answer explanation

Alex has written the wrong hundreds digit. He has forgotten to add the regrouped hundred.

Eva and baby Elliott have a total length of 585 cm. Choose the correct lengths for Eva and her baby.

• Eva is 399 cm long.

• Eva is 389 cm long.

• Baby Elliott is 196 cm long.

• Baby Elliott is 176 cm long.

• Baby Elliott is 156 cm long.

Answer explanation

Eva is 389 cm long and baby Elliott is 196 cm long.