Answer:
see attached image
Step-by-step explanation:
Answer: 3/8
Step-by-step explanation: 3/4 divided by 2 or .75/2
2.5/0.2=12.5
2.5 times 12.5=31.25
The actual height of the building is 31.25 cm
Answer:11
Step-by-step explanation:
Boys : girls=7:1
Sum of ratio=7+1=8
Let them number of girls be y
Then they number of boys=y+66
Total number of pupils=y+y+66
Total number of pupils=2y+66
Number of girls=(girls ratio)/(sum of ratio) x (total number of pupils)
y=1/8 x (2y+66)
Cross multiply
y x 8=2y + 66
8y=2y + 66
Collect like terms
8y-2y=66
6y=66
Divide both sides by 6
6y/6=66/6
y=11
The number of girls is 11