Rectangular cards 8×5 cm are cut from square chart 60 cm side. How many cards? What area left?
Step 1: Understand the sizes
Square chart side = (60 ext{cm})
One rectangular card = (8 ext{cm} imes 5 ext{cm})
Step 2: Find the area of the chart
( ext{Area of chart} = 60 imes 60 )
( = 3600 ext{cm}^2 )
Step 3: Find the area of one card
( ext{Area of one card} = 8 imes 5 )
( = 40 ext{cm}^2 )
Step 4: How many such cards fit (by area)?
( ext{Number of cards} = dfrac{3600}{40} )
( = 90 )
Step 5: Check leftover area
( ext{Used area} = 90 imes 40 = 3600 ext{cm}^2 )
( ext{Leftover area} = 3600 - 3600 = 0 ext{cm}^2 )
Answer: 90 cards can be cut, and no area is left.