Question

Dacă a÷b=3;c÷a=2 și c-b=45 calculează 2a+a+3c

Answer 1

a÷b=3....a=3b....a=3b....a=3×9=27

c÷a=2....c=2a....c=2×3b....c=6b...c=6×9...c=54

c-b=45....6b-b=45....5b=45....b=45:5....b=9

2a+a+3c=2×27+27+3×54=
54+27+162=
243

Answer 2

a: b = 3 => a = 3×b
c : a = 2 => c = 2×a
c - b = 45
a |___|___|___|
b |___|
c |___|___|___|___|___|___|
Avem 6 segmente egale - 1 segment egal = 5 segmente egale = 45
45 : 5 = 9 (un segment egal)
a = 3×9 = 27
b = 9
c = 6×9 = 54

Verificare:
27:9 = 3
54 : 27 = 2
54 - 9 = 45

a = 27
b = 9
c = 54

2a + a + 3c = 2×27+27+3×54 = 54+27+162 = 243