Rests in 10/16 time

Question

I am confused about a solution to a question in my music theory exercise book. The answer is shown in an image below (the one in 10/16 time). From what I understand, the rests should fit into the beats of Strong-Weak-Medium-Weak.

Doesn't it make more sense to have the dotted eighth rest on the medium beat instead of the final weak beat? That way the sixteenths are grouped like 3-2-3-2. Is my thinking wrong here? I am new to this so I could be mistaken or just unaware. Perhaps both 3-2-3-2 and 3-2-2-3 are valid but one is preferable? Could someone shed some light on my confusion here? Thank you in advance.

Edit: It is probably too late now, but here is the question from the book. Next time, I'll be sure to include the question too.

Answer 1

NOTE: See bottom of post for edit in light of new information since the original answer

There are two sets of pulses involved here: the "small" pulses -- in groups of 3 or 2 -- and the "large" pulses -- of which the exercise, as you've described it, requires four total. It sounds like you're conflating the "large" pulse strength with the duration of that "large" pulse (that is, its 3-ness or 2-ness). But they're independent. Whether the rhythmic ("small") grouping is 3-2-3-2 or 2-3-2-3 or 3-2-2-3, the metric ("large") pulse maintains its own pattern. When the meter comprises four main pulses, it frequently follows the strong-weak-medium-weak pattern (frequently, but not always).

In the specific example you're showing, the key to the "small" grouping is the duration of the rests: so, 3-2-2-3.

strong  weak  medium  weak
   3     2       2      3

Here are some additional examples of how the notation reflects the "small" groupings, but the metric pulse (the "large" groupings) remains the same.

X:0
T:3+2+3+2
K:C
M:10/16
L:1/16
"strong"F z z "weak"z2 y"medium"z3 yy"weak"z2 |

X:0
T:2+3+2+3
K:C
M:10/16
L:1/16
"strong"F z "weak"z3 y"medium"z2 yy"weak"z3 |

X:0
T:3+3+2+2
K:C
M:10/16
L:1/16
"strong"F z z "weak"z3 y"medium"z2 yy"weak"z2 |

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EDIT

Since posting the answer, the textbook question that prompted the OP is posted. As @Mycroft points out below (comments), and assuming every measure is expected to use the same rhythmic grouping, the first grouping must be 3, because the second measure contains a dotted eighth-note.

Based on this and this (rules for rest placement), the initial 3-groups must be filled out with sixteenth rests. Since the rests begin on a weak (part of the rhythmic) beat, we must fill the space with sixteenth rests.

Beyond that is conjecture.

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Conjecture...

I believe the book is at fault for not specifying the possibility of multiple answers. However, if there are rules demanding 3+2+2+3, then I would suggest these:

1. A compound meter with an even number of beats should be divided into equal parts, so in the case of 10/16, 5+5. This requires 3+2 for the first half-measure.
2. Empty space should be filled with rests in ascending order of duration, corresponding to the "large" metric beats. So that would mean 2+3 for the second half of the measure, rather than 3+2.