Question

Solve the proportion for N:

Answer 1

$1.\rightarrow \frac{5}{12}=\frac{35}{N}\\\\\rightarrow 5N=35 \times 12\\\\\rightarrow N=\frac{420}{5}\\\\\rightarrow N=84\\\\2.\rightarrow \frac{7}{18}=\frac{N}{9}\\\\\rightarrow 18N=7 \times 9\\\\\rightarrow N=\frac{63}{18}\\\\\rightarrow N=\frac{7}{2}\\\\N=3.5\\\\3.\text{Amount paid for the job}=240\\\\\text{Amount spent on supplies}=240 \times \frac{2}{5}\\\\=48 \times 2\\\\=96$

---Amount spent on supplies if electrician pays two fifth of the amount he charges for a job for supplies =$ 96

4.

h=Headlight

t=Taillight

→h+t=1000------(1)×13.95

→13.95 h +13.95 t=13950-----(1)

→13.95 h+7.55 t=9342------(2)

equation (1) - equation (2)

  6.40 t=4608

t=720------(Taillight Bulb)

Replacing ,t by 720 in equation 1,

h+720=1,000

h=1,000 -720

h=280---(Headlight bulbs )

→5.

Cost of 5 dozen of roses =$62.50

Cost of a dozen of rose=$ 12.50-----Dividing both sides by,5

Cost of 8 dozen of rose=$ 12.50 × 8----Multiplying both sides by,8

       =$ 100.00

Answer 2

For the first three questions
5/12 = 35/N
Rearrange: N = 35 / (5/12) = ( 35 / 0.4167 ) = N = 83.99

7/18 = N / 9
Rearrange: N = (7/18)* 9 = 3.5

(2/5) * 240 = 96
He spent $96 on supplies