Hey <griniegenie>

Appreciate that you can provide <Answerkey> in future, if any. Thanks.

Following are my worked solutions:

Q1

s(X) : s(Y)

80 : 100

4 : 5

Given that distance is constant, the time taken ratio is the reverse / inverse of the speed ratio. Hence,

t(X) : t(Y)

5 : 4

1u --> (3/4)hr

To travel the entire distance,

X took 5u --> 5 × (3/4) = (15/4)hr

Y took 4u --> 4 × (3/4) = 3hr

Hence, distance = 80 × (15/4) = 300 km

t(when both cars met) = Distance Apart ÷ Sum of Speeds

= 300 ÷ 180 = (5/3) hr = 1 hr 40 min

Time (when both X, Y met):

09 45 + 1 40 = **11 25**

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Q2.

<Cost>

V |------------|

F |------------<- 901 ->|

Given that both vitamins (V) and fish Oil (F) cost $2363, we have ...

2u --> 2363 - 901 = 1462

1u --> 1462 ÷ 2 = 731

hence, F = 731 + 901 = 1632 ; V = 731

Given number of bottles bought,

F : V

4 : 1

4u (F) --> 1632

1u (F) --> 408

1u (V) --> 731

Given each bottle of fish oil (F) cost $19 less than each bottle of vitamins (V),

V - F = 19

Cost Difference between 1u of V and 1u of F:

731 - 408 = 323

Number of bottles of V:

323 ÷ 19 = 17

Cost of 1 bottle of V:

731 ÷ 17 = **$43**

==========

Trust these help.

Do let me know again if these are different from your <Answerkey> or if there's further clarification.

Cheers,

Edward