A roll of adhesive tape is wound round a central cylindrical core of radius 3cm. the outer radius of a roll containing 20m of tape is 4cm. Approximately, what is the outer radius of a roll containing 80m of tape.
A) 5cm
B)5.5cm
C)6cm
D)7cm
E)12cm
A) 5cm
B)5.5cm
C)6cm
D)7cm
E)12cm
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7cm...75% chance that's right
the cores radius is 3cm and it states that 20m of tape (with a radius of 4cm total) is wound around the core...so in total (core and tape) has a radius of 4 cm which means the 20m of tape added 1cm to the radius. your looking for 80m of tape. 20m of tape is = +1cm on the radius. 4x20=80 so add 4cm onto the 3cm already there and now it has a radius of 7 cm
the cores radius is 3cm and it states that 20m of tape (with a radius of 4cm total) is wound around the core...so in total (core and tape) has a radius of 4 cm which means the 20m of tape added 1cm to the radius. your looking for 80m of tape. 20m of tape is = +1cm on the radius. 4x20=80 so add 4cm onto the 3cm already there and now it has a radius of 7 cm