Here are the solutions to the problems:
r)
Step 1: Write the ratio of the mass of the stone to the mass of the dog.
Ratio=Massofstone:Massofdog
Ratio=30kg:90kg
Step 2: Simplify the ratio by dividing both sides by their greatest common divisor, which is 30.
3030:3090
1:3
The ratio is 1:3.
s)
Step 1: Find the total number of parts in the ratio.
4+5=9parts
Step 2: Find the value of one part.
9parts720=80perpart
Step 3: Calculate each share.
First share: 4×80=320
Second share: 5×80=400
The shares are 320and400.
Problem 2
(i)
Step 1: Convert the mixed number to an improper fraction.
121=23
Step 2: Write the proportion.
q:23=20:30
Step 3: Express the proportion as a fraction.
23q=3020
Step 4: Simplify the right side of the equation.
23q=32
Step 5: Multiply both sides by 23 to solve for q.
q=32×23
q=1
The value of q is 1.
(ii)
Step 1: Write the proportion.
43:21=W:16
Step 2: Express the proportion as a fraction.
2143=16W
Step 3: Simplify the left side of the equation.
43÷21=43×12=46=23
So, the equation becomes:
23=16W
Step 4: Multiply both sides by 16 to solve for W.
W=23×16
W=3×8
W=24
The value of W is 24.
(iii)
Step 1: Write the proportion as a fraction.
a+3a=65
Step 2: Cross-multiply.
6×a=5×(a+3)
6a=5a+15
Step 3: Subtract 5a from both sides.
6a−5a=15
a=15
The value of a is 15.
(iv)
Step 1: Write the expenditure of Asha and Mbaga.
Asha's expenditure = sh. 24000
Mbaga's expenditure = sh. 12000
Step 2: Form the ratio of their expenditure (Asha : Mbaga).
24000:12000
Step 3: Simplify the ratio by dividing both sides by their greatest common divisor, which is 12000.
1200024000:1200012000
2:1
The ratio of their expenditure is 2:1.
(v)
Step 1: Convert the decimal and fraction to simpler forms.
0.5=21
3015=21
Step 2: Write the proportion with the simplified terms.
21:21=60:B
Step 3: Since the ratio on the left side is 1:1, the ratio on the right side must also be 1:1.
1:1=60:B
Step 4: This means B must be equal to 60.
B=60
The value of B is 60.
(vi)
Step 1: Find the total number of parts in the ratio.
2+3+5=10parts
Step 2: Find the value of one part.
10parts1870kg=187kgperpart
Step 3: Calculate each share.
First share: 2×187kg=374 kg
Second share: 3×187kg=561 kg
Third share: 5×187kg=935 kg
The shares are 374kg,561kg,and935kg.