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estimate the perimeter of a school chalkboard, measuring 76 cm by 46 cm. Give your answer to the nearest ten​

User Sana
by
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2 Answers

1 vote

Answer:

260

Explanation:

76 rounded to 1 s.f. is 80

46 rounded to 1s.f. is 50

80+50+80+50= 260

Hope this helps!

User Abdelazeem Kuratem
by
5.0k points
9 votes

Answer:

240 cm (to the nearest ten)

Explanation:

perimeter of a rectangle = 2W + 2L

where W is the width and L is the length

To estimate the perimeter, first round the components to the nearest ten then carry out the calculation.

Given:

  • width = 46 cm ≈ 50 cm (nearest ten)
  • length = 76 cm ≈ 80 cm (nearest ten)

⇒ estimated perimeter = 2 x 50 + 2 x 80 = 100 + 160 = 260 cm

Alternatively, to calculate the actual perimeter and then round the answer to the nearest ten:

⇒ actual perimeter = 2 x 46 + 2 x 76 = 92 + 152 = 244 cm

⇒ perimeter = 240 cm (to the nearest ten)

User Pete Schlette
by
5.8k points