AMO 2019, Primary 4 Contest

Find the value of the following expression: 3 × 5 + 5 × 7 + 7 × 9 + 9 × 11

• 150

• 160

• 170

• 180

How many three-digit numbers have a sum of digits equal to 6?

• 10

• 15

• 21

• 28

Find the value of the following expression: (7643 + 6437 + 4376 + 3764) ÷ 110

• 210

• 220

• 230

• 240

A 3x3 grid is filled with integers. Which number needs to be changed so that the sum of the numbers in each row, the sum of the numbers in each column, and the sum of the numbers in each diagonal are all equal?

• Number in the first row, first column

• Number in the second row, second column

• Number in the third row, third column

• Number in the first row, third column

A MOEMS tile has a shape resembling the letter M as shown. It is a 5x5 square with two 4x1 rectangles removed. If the area of the MOEMS tile is 153 cm², what is its perimeter in cm?

• 34 cm

• 36 cm

• 38 cm

• 40 cm

Isabella has stacked unit cubes in the corner of a room as shown in the image. If Isabella continues this pattern to stack seven cubes high instead of four cubes, how many more cubes does she need?

• 10 cubes

• 20 cubes

• 30 cubes

• 40 cubes

What are the first two digits of the number Randal if the product of the number Randal and 101 is 2488842 and this number reads the same forwards and backwards?

• 248

• 252

• 253

• 258

What are the last two digits of the key combination?

• 688

• 884

• 448

• 488

Find the sum of the digits of the product 555 x 555.

• 15

• 25

• 30

• 35

Chloe has a rectangle made of construction paper. She folds the rectangle in half to create another rectangle. She then folds the resulting rectangle in half to create a square that is 3 cm x 3 cm. What is the area (cm²) of Chloe's original rectangle?

• 36 cm²

• 72 cm²

• 144 cm²

• 288 cm²