Matemática Elementar

Problema 1

Use a ruler to measure. A crayon is $9$ centimeters long. A pencil is $15$ centimeters long.

a) How much longer is the pencil than the crayon?

b) If you put the crayon and the pencil end-to-end, how long would they be together?

Problemas

1. Use a ruler to measure. A crayon is $9$ centimeters long. A pencil is $15$ centimeters long.

a) How much longer is the pencil than the crayon?

b) If you put the crayon and the pencil end-to-end, how long would they be together?

2. What time is it? Write the time shown:

a) The hour hand points to $3$ and the minute hand points to $12$ .

b) The hour hand is between $7$ and $8$ , and the minute hand points to $6$ .

c) The hour hand points to $12$ and the minute hand points to $12$ .

3. Name each shape and tell how many sides it has:

a) A shape with $5$ sides and $5$ corners.

b) A shape with $6$ sides and $6$ corners.

c) A shape with $4$ sides where all sides are different lengths.

4. Tom measured his book with a ruler. It is $22$ centimeters long. His notebook is $28$ centimeters long.

a) How much shorter is the book than the notebook?

b) Which tool should Tom use to measure: a ruler or a yardstick? Why?

5. Look at the shapes and answer:

a) A triangle has $\underline{\quad}$ sides. Is a triangle a quadrilateral? Why or why not?

b) A square has $\underline{\quad}$ sides. Is a square a quadrilateral?

c) Name two shapes that are quadrilaterals.

d) A stop sign has $8$ sides. What is this shape called?

Gabarito — Measurement and Geometry

1. a) Find the difference: $15 - 9 = 6$ centimeters. The pencil is $6$ cm longer than the crayon.

b) Add the lengths: $9 + 15 = 24$ centimeters. Together they would be $24$ cm long.

2. a) Hour hand on $3$ , minute hand on $12$ means exactly $3{:}00$ (three o'clock).

b) Hour hand between $7$ and $8$ , minute hand on $6$ means $7{:}30$ (seven thirty). The minute hand on $6$ always means $30$ minutes past the hour.

c) Both hands on $12$ means exactly $12{:}00$ (twelve o'clock — noon or midnight).

3. a) A shape with $5$ sides and $5$ corners is a pentagon.

b) A shape with $6$ sides and $6$ corners is a hexagon.

c) A shape with $4$ sides (even if they are different lengths) is a quadrilateral. All four-sided shapes are quadrilaterals.

4. a) $28 - 22 = 6$ centimeters. The book is $6$ cm shorter than the notebook.

b) Tom should use a ruler because both objects are small enough to measure with a standard ruler (which is usually $30$ cm). A yardstick is better for larger objects like a table or a door.

5. a) A triangle has $3$ sides. It is not a quadrilateral because a quadrilateral must have exactly $4$ sides, and a triangle only has $3$ .

b) A square has $4$ sides. Yes, a square is a quadrilateral because it has exactly $4$ sides.

c) Two quadrilaterals: a square and a rectangle (other correct answers include rhombus, trapezoid, or parallelogram).

d) A shape with $8$ sides is called an octagon.