Use this diagram to find the required measures. 1 = 30°, 2 = 30°, 3 =

if thisa is a triangle then 180-30+30 = 120 degree and we say all angles on a triangle add up to 180

Then reaply the rule changing 180 to 360 on all 4 sided shapes

180(n-2) to all other shapes.

ie) pentagon 180(n-2) = 540

continue with 540-30-30 = 480 etc

Step-by-step explanation:

step by step resolutions

1) n+n+1+n+2=51

3n+3=51

3n=48

n=16

the three numbers are 16, 17 and 18.

2) x+15=4x

3x=15

x=5

radha is now 5 years old

3) the two digits are x and y.

y=3x

(10x+y)+(10y+x)=88

y=3x

11x+11y=88

y=3x

x+y=8

x+3x=8

x=2

the original number can be either 28 or 82.

4) n+(n+2)+(n+4)=48

3n+6=48

3n=42

n=14

the numbers are 14, 16 and 18.

5) y=x+3

10y+x+10x+y=143

y=x+3

11x+11y=143

y=x+3

x+y=13

x+x+3=13

2x=10

x=5

the original number can be 57 or 75.

hope this !