Răspuns:
n = 45
Explicație pas cu pas:
2n+3p = 150
n = 10a+b
a·b = p
20a+2b+3ab = 150 ; a ∈ {1 , 2 ...,9} ; b ∈ {1 , 2 ,...,9}
a = 1 => 20+2b+3b = 150 => 5b = 130 => b = 26 > 9 , nu convine
a = 2 => 40+2b+6b = 150 => 8b = 110 => b ∉ N
a = 3 => 60+2b+9b = 150 => 11b = 90 => b ∉ N
a = 4 => 80+2b+12b = 150 => 14b = 70 => b = 5
a = 5 => 100+2b+15b = 150 => 17b = 50 => b ∉ N
a = 6 => 120+2b+18b = 150 => 20b = 30 => b ∉ N
a = 7 => 140+2b+21b = 150 => 23b = 10 => b ∉ N
=> n = 45
2·45+3·4·5 = 90+60 = 150 = corect.
