From the diagram above, what is the area of the shaded parts?
We can take the squares roll by roll, starting from roll 1 (the topmost):
Roll 1: The total area of roll 1 is 4 unit sq. (1 sq. unit x 4), But the half of the area is not shaded so ¹⁄₂ x 4 sq, unit = 2 sq. unit And also the first square as the bottom half not shaded = ¹⁄₂ x 1 sq. unit = ¹⁄₂ sq. unit
So, shaded part of roll 1 is = 2 sq. unit - ¹⁄₂ sq. unit = 1¹⁄₂ sq. unit
Roll 2: We have a whole square and half of a square shaded = 1¹⁄₂ sq. unit
Roll 3: We have only half of a square shaded = ¹⁄₂ sq. unit
Total area shaded = 1¹⁄₂ +1¹⁄₂ + ¹⁄₂ = 3¹⁄₂ sq. unit
From the diagram above, what is the area of the shaded parts?
We can take the squares roll by roll, starting from roll 1 (the topmost):
Roll 1: The total area of roll 1 is 4 unit sq. (1 sq. unit x 4), But the half of the area is not shaded so ¹⁄₂ x 4 sq, unit = 2 sq. unit And also the first square as the bottom half not shaded = ¹⁄₂ x 1 sq. unit = ¹⁄₂ sq. unit
So, shaded part of roll 1 is = 2 sq. unit - ¹⁄₂ sq. unit = 1¹⁄₂ sq. unit
Roll 2: We have a whole square and half of a square shaded = 1¹⁄₂ sq. unit
Roll 3: We have only half of a square shaded = ¹⁄₂ sq. unit
Total area shaded = 1¹⁄₂ +1¹⁄₂ + ¹⁄₂ = 3¹⁄₂ sq. unit
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