Tolong bantu ka soal ujian
L selimut tabung = 5.280
2 × phi × r × t = 5.280
2 × 22/7 × r × 30 = 5.280
1.320/7 × r = 5.280
r = 5.280 ÷ 1.320/7
r = 5.280 × 7/1.320
r = 4 × 7/1
r = 28/1
r = 28 cm
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L alas tabung :
= phi × r²
= 22/7 × 28 × 28
= 22/1 × 4 × 28
= 22 × 4 × 28
= 88 × 28
= 2.464 cm²