This "problem" occurs in two places, Ex 25 and 37. Let us examine the detailed description as per Ex 25 which is reproduced in the appendix below.
The cardinal features of the menorah were:
- There was to be a central lampstand with three branches either side (V32) - a total of seven
- Each of the side branches has three cups (V33)
- The central stem had four cups (V34)
- There was a lamp atop each of the branches and the central stem (V37) - seven in all
Thus, there were a total of 22 cups in total - three on each of the six side branches and four on the central stem.
The word "cup" here is גְּבִיעַ (gabia) which only occurs 14 times in the OT as follows:
- Gen 44:2, 12 16, 17 - Josephs silver cup
- Ex 25:31, 33, 34 - cups on the branches of the menorah
- Ex 37:17, 19, 20 - cups on the branches of the menorah
- Jer 35:5 - Rechabites' cups
In commenting on Ex 25:31, Ellicott says:
(33) Three bowls made like unto almonds.—Or, three cups like almond
blossoms. It is not quite clear if these were consecutive, or if each
cup held a “knop” (pomegranate), on which followed a (lily) blossom.
On the whole Reland’s representation accords best with the latter
view.
APPENDIX - Ex 25:31-40
31 Then you are to make a lampstand of pure, hammered gold. It shall be made of one piece, including its base and shaft, its cups,
and its buds and petals.
32 Six branches are to extend from the sides of the lampstand—three on one side and three on the other.
33 There are to be three cups shaped like almond blossoms on the first branch, each with buds and petals, three on the next branch, and
the same for all six branches that extend from the lampstand.
34 And on the lampstand there shall be four cups shaped like almond blossoms with buds and petals.
35 For the six branches that extend from the lampstand, a bud must be under the first pair of branches, a bud under the second pair, and
a bud under the third pair.
36 The buds and branches are to be all of one piece with the lampstand, hammered out of pure gold.
37 Make seven lamps and set them up on the lampstand so that they illuminate the area in front of it.
38 The wick trimmers and their trays must be of pure gold.
39 The lampstand and all these utensils shall be made from a talent of pure gold.i
40 See to it that you make everything according to the pattern shown you on the mountain.