AMO 2017 Grade 3

What is the value of 20 + 19 + 18 + 17 + 16 - 15 - 14 - 13 - 12 - 11?

What is the value of (70 × 4) - (80 × 3) + (60 × 5)?

The sum of the digits of the number 216 is 9. What is the least number greater than 216 whose sum of the digits is 9?

Find the value of 98 - 87 + 76 - 65 + 54 - 43 + 32 - 21 + 10.

Sandy multiplies 2 × 5 × 7 × 2 × 5 × 7 × 2 × 5 and writes the product as a whole number. What is the sum of the digits of this number?

The first row has 2 dots:

The second row has 4 dots:

The third row has 6 dots:



More rows are added. Each additional row has 2 more dots than the row before it. How many dots will there be in the first 10 rows combined?

Dillon works at the park once every three days. William works at the park once every six days. Francis works at the park once every eight days. They all worked together on Thursday. The park is open every day. On what day of the week will they all next work together?

(If your answer is Monday, write 001; if it is Tuesday, write 002; and so on)

Summer vacation lasts for 55 days. During summer vacation, what is the greatest number of Fridays that could occur?

What is the greatest multiple of 25 that has exactly 3 digits?

Jake is John’s father. The sum of their ages is 44. In 14 years Jake will be twice as old as John. How old will John be in 14 years?

At Springfield Elementary School, a shelf contains either 4 math books or 9 spelling books. On 15 shelves at Springfield Elementary School, there are 72 spelling books and some number of math books. All 15 shelves are full. How many math books are there on the shelves?

The cost of 3 pencils and 2 markers is \$13. The cost of 2 pencils and 3 markers is \$12. What is the total cost of 7 pencils and 7 markers?

A certain book has its pages numbered from 1 to 50. Then any page number that contains the digit “3” is entirely erased. What is the sum of all of the numbers that were erased?

Given:



What is the value of ○?

The cube at the right is constructed of same sized figures as shown. How many figures does the cube contain?