There are many ways.

1. In Speedy

• type CTRL-3, and the first note/chord as an eighth note
• type the second note/chord as an eighth
• back arrow to the first note/chord and change the note value to a quarter.

2. In Simple

• type the first note/chord as an eighth
• press 9 to indicate an eighth triplet
• add the second eighth note
• change the first note/chord to a quarter

In either case, if you do this at the end of a measure, you may need to turn off "Check for extra notes." 

You can of course type in the quarter-eighth combination and then use the triplet tool to add the eighth-note 3:2 triplet.

(And there are other ways....)

(Changing brackets to slurs, etc. can be handled after entry using the triplet tool or the tuplet option in the Utilities > Change > Tuplet menu item.)

Thanx awfully

In the Speedy Entry Tool, even faster than J Adrian Verkouteren’s solution:

CTRL-1 (opens the Tuplet Definition which defaults to 3 Eighths in the space of 2 Eighths)

Return (OK!)

5 (entering the quarter)

4 (entering the eighth)

Ok, I do as Peter suggested. I am in 4/4 and the first two beats of the measure are claimed. I select Speedy entry and Finale fills in the half rest.

I select the half rest in speedy entry and CTRL-1 then 5, 4 and I get a quarter rest and an eighth rest, The half rest is sort of scooched over. I repeat and select the half rest, then 5, 4 and I get a quarter rest and the half rest stays there (under the triplet bracket) but I have some extra rests in the next measure. I replace the first quarter rest and eighth rest with their respective note values. so far so good. Then I replace the next quarter rest with a quarter note and the half rest with an eighth note looks ok. Plays back ok. So I just have to clean up the mess in the next measure and enter it's notes. Seems like an odd way of doing business.

… I select the half rest in speedy entry and CTRL-1 then 5, 4 and I get a quarter rest and an eighth rest …

Selecting the half rest is the way you work in the Simple Entry Tool’s sub-tool Tuplet Tool:

First add the entry, and next modify the entry, to make a triplet.

In the Speedy Entry Tool’s sub-tool Tuplet Tool you do it “the other way around”:

First, specify the triplet - via CTRL-1 and Return.

Next, add the entry (entries).

In Other Words:

Before you begin creating the triplet, delete the half rest that Speedy filled in.

The half rest is only filled in because you switch to Speedy Entry from another tool (probably Simple Entry).

You will not get this problem if you enter the entire measure (also the first two beats) from Speedy Entry.

Or, you can use Simple Entry and enter it with no problems. Which entry method do you prefer?