Jika FPB (2a 2b)-20. KPK (2a 2b)- 120. Maka ab=

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Jika FPB (2a 2b)-20. KPK (2a 2b)- 120. Maka ab=

Jawab:

Penjelasan dengan langkah-langkah:

Cara 1 :

displaystyle mathrm{KPK(2a,2b)} = frac{2acdot 2b}{ mathrm{FPB(2a,2b)}} \120 = dfrac{4cdot ab}{20}\120 = dfrac{ab}{5}\\Huge{boxed{boxed{boldsymbol{ab = 600}}}

Cara 2:

FPB(2a,2b) = 20 = 2² × 5 => 2a = 2² × 5 × k => a = 10k

b = 10n

catatan : k dan n bilangan prima

KPK(2a,2b) = KPK(20k,20n) = 20kn = 120

kn = 6 = 2 × 3 => k = 2 atau 3, n = 3 atau 2

ab = 100kn = 600