Answer: N= 375, C= 875
Step-by-step explanation: Let Canadian stamps=C
Let International stamps=N
C=875 and N=375
C - 500=N, .70(N + C) =C
Solve the following system:
{C-500 = N | (equation 1)
0.7 (C+N) = C | (equation 2)
Express the system in standard form:
{-N+C = 500 | (equation 1)
0.7 N-0.3 C = 0 | (equation 2)
Add 0.7 × (equation 1) to equation 2:
{-N+C = 500 | (equation 1)
0 N+0.4 C = 350 | (equation 2)
Divide equation 2 by 0.4:
{-N+C = 500 | (equation 1)
0. N+C = 875. | (equation 2)
Subtract equation 2 from equation 1:
{-N+0 C = -375. | (equation 1)
0 N+C = 875. | (equation 2)
Multiply equation 1 by -1:
{N+0 C = 375. | (equation 1)
0 N+C = 875. | (equation 2)
Collect results:
Answer: | N = 375 and C=875
