a. Y = C + I + G = 200 + 0.75(Y - 100) + 200 - 25r + 100						r	Y
Y = 200 + 0.75Y - 75 + 200 -25r + 100						0	1700
Y - 0.75Y = 425 -25r						1	1600
0.25Y = 425 - 25r						2	1500
Y =1700 - 100r This is IS equation						3	1400
						4	1300
						5	1200
						6	1100
						7	1000
						8	900
b. M/P = Y - 100r
1000/2 = Y - 100r
500 = Y - 100r
Y = 500 + 100r This is LM equation						r	Y
						0	500
						1	600
						2	700
						3	800
						4	900
						5	1000
						6	1100
						7	1200
						8	1300
c. Set Y = Y
1700 - 100r = 500 + 100r
1200 = 200r
r = 1200/200 = 6
Y = 1700 - 600 = 1100
d. Y = C + I + G = 200 + 0.75(Y - 100) + 200 - 25r + 150
Y = 200 + 0.75Y - 75 + 200 -25r + 150
Y - 0.75Y = 475 -25r
0.25Y = 475 - 25r
Y =1900 - 100r This is new IS equation				The IS curve shifts up by 200
Set Y = Y
1900 - 100r = 500 + 100r
1400 = 200r
r = 1400/200 = 7
Y = 1900 - 700 = 1200
e. M/P = Y - 100r
1200/2 = Y - 100r
600 = Y - 100r
Y = 600 + 100r This is new LM equation				The LM curve shifts up by 100
Set Y = Y
1700 - 100r = 600 + 100r
1100 = 200r
r = 1100/200 = 5.5
Y = 1700 - 550 = 1150
f. M/P = Y - 100r
1000/4 = Y - 100r
250 = Y - 100r
Y = 250 + 100r This is new LM equation				The LM curve shifts down by 250
Set Y = Y
1700 - 100r = 250 + 100r
1450 = 200r
r = 1450/200 = 7.25
Y = 1700 - 7250 = 975
g. M/P = Y - 100r									Y	P
1000/P = Y - 100r									1350	1
100r = Y - 1000/P									1100	2
r = Y/100 - 10/P		This is LM equation expressing r in terms of Y							1016.667	3
From IS equation, solve for r in terms of Y									975	4
100r = 1700 - Y									950	5
r = 17 - Y/100									933.3333	6
Set r = r									921.4286	7
Y/100 - 10/P = 17 - Y/100									912.5	8
2Y/100 = 17 + 10/P
Y/50 = 17/P
Y = 850 + 500/P
This aggregate demand curve will shift if fiscal or monetary changes, as in parts (d) and (e).