Question

Dan D. Lyons recorded two temperature measurements for his experiment. One of the measurements is 2/3 of another measurement. If the sum of the measurements is -30°C what two measurements were recorded?

Answer 1

`-18^(\circ)C,`
`-12^(\circ)C`

Explanation:

Let the first measurement be x°C. The second measurement is
`(2)/(3)` of the first one, then the second measurement is
`(2)/(3)x^(\circ)C.`

If the sum of the measurements is -30°C, then

`x+(2)/(3)x=-30.`

Multiple the whole equation by 3:

`3x+2x=-90,\\ \\5x=-90,\\ \\x=-18^(\circ)C.`

Another measurement is

`(2)/(3)\cdot (-18^(\circ))=-12^(\circ)C.`