Answer:
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Let the cost of chickens be c and donkeys be d.
We have equations according to given details:
- 5c + 3d = 215,
- 7c + 2d = 202.
Solve the system by elimination, multiply the first equation by 2 and the second one by 3, then subtract:
- 2*5c + 2*3d - 3*7c - 3*2d = 2*215 - 3*202
- 10c + 6d - 21c - 6d = 430 - 606
- -11c = - 176
- c = 176/11
- c = 16
Find the value of d:
- 5*16 + 3d = 215
- 80 + 3d = 215
- 3d = 135
- d = 135/3
- d = 45
Find the cost of 4 chickens and 5 donkeys:
- 4*16 + 5*45 =
- 64 + 225 =
- 289
